The Book: JoJo's Bizarre Adventure 4th Another Day

The Book: JoJo's Bizarre Adventure 4th Another Day is a novel written by Otsuichi, with artwork by Hirohiko Araki. It was released to coincide with the 20th anniversary of JoJo's Bizarre Adventure.

The story serves as a sequel to Diamond is Unbreakable. The novel shows the events following a mysterious death in Morioh, alternating between the perspectives of Koichi Hirose, Chiho Futaba and Takuma Hasumi, two original characters and the protagonists of the novel. Takuma's Stand is called The Book and possesses the power to record everything he sees or feels into a small, leather-bound book. Josuke and several other Diamond is Unbreakable characters appear as side characters. A third storyline, from the perspective of Akari Hirai, another original character, takes place in 1981.

Summary
The novel presents itself as a, skipping around between different people at different points in time portrayed in a non-chronological order.

 {{Tabber
 * Prologue|

Introitus
In the town of Morioh, another day begins for Koichi Hirose who observes the townspeople as they go by. Koichi narrates about the rumor of the man who lived on the power lines. One day, after initially believing it was only a tale, he decided to use his binoculars to find the power line in question. Unsurprisingly, he saw the hermit Stand user Toyohiro Kanedaichi living a seemingly normal life several meters above the ground. His "home" is complete with of a frying pan, a portable stove, and even a futon. Despite being unable to leave the tower, he manages to sustain himself and has lived a full life for months with the help of the people coming to visit him and give him candies and spices. At one point, he became known as the iron tower man of Morioh.

Meanwhile, Chiho Futaba and Takuma Hasumi walk home together, discussing about the man on the iron tower. When Chiho asks if it is ever possible to live a long life without leaving the tower, Takuma tells her the story about a woman who had been living in between two buildings for a year. Chiho says nothing else and wonders whether the story was true or merely another local urban legend.

The prologue ends on the night of a school closing ceremony, with Chiho stabbing a loved one in the kitchen of their home. Before dying, the person calls out the name of their ability: Memory of Jet.
 * Chapter 1|

Kyrie
On January 4, 2000, Koichi Hirose meets up with Rohan Kishibe at a convenience store. Koichi watches Rohan as he scatters biscuits laced with sleeping drugs to find a cat that had made a mess in his workstation. With the culprit found, Rohan calls the animal shelter. The two find a a disheveled cat covered in blood exit the convenience store with a biscuit in its mouth, before succumbs to the drugs.

The story jumps to Akari Hirai, a woman from Morioh who later meets a man named Teruhiko Ogami. One day in 1981, Akari receives a mysterious phone call from Ogami's lover, Hanae Orikasa, who says that Ogami had been illegally replacing building materials with substandard ones. After investigating, Akari doesn't see any illegal blueprints but does find a duffle bag with at least 50 million yen inside. Ogami meets with her on the building's roof to discuss this but immediately pushes her off the roof to kill her. Akari wakes up after a few hours, awoken by the rain, and finds herself in an alleyway between two buildings. With no ways to escape the narrow space, she decides to call for help the next morning when everyone goes to work. A while later, she hears Ogami's voice from above, congratulating her on her fortune.

In the present day, Koichi and Rohan examine the bloodied cat. They find the cat's collar and decide to go to the owner's house. At the house, they discover a corpse in the living room and call the police. Once the police arrives, Koichi tells them that the victim must be Hanae Orikasa based on the name on the cat's collar.

The story introduces Chiho Futaba. On October 21, 1995, a 12-year-old Chiho decides to run away from home. She is robbed by a high school delinquent in a bus terminal, but was saved by a boy whose face she could not clearly remember. Her last memories of the encounter were with the boy pulling out a knife and an ear with a gold earring on the ground. In middle school, she discovers an interest in becoming an author after her parents' divorce and later attends Budogaoka High School. In 1999, at the Morioh Municipal Library, also known as "Thorn Building", Chiho notices the same boy who saved her from that delinquent four years ago. The boy impresses her after immediately finding the exact book with only one look at a ripped page, as he had all of the books in the library memorized. Chiho asks him about the events in 1995, but he says she must have confused him with someone else. He introduces himself as the 17-year-old Takuma Hasumi. In just a few months, they become acquaintances to the point that Chiho soon notices parts of his personality such as his hobby of visiting all sorts of places, from bookstores to one specific house, later revealed to be Akari Hirai's house.

On June 10, 1982, a baby is discovered on the steps of a temple. He is named Takuma Hasumi after a horse-shaped birthmark on his shoulder. After moving to an orphanage, a 5-year-old Takuma meets a 3-year-old child named Crybaby Boy. Takuma took pity upon Crybaby Boy and would tell him stories at night to make him stop crying. Takuma's ability to recount stories perfectly catches the attention of adults and determines him as a genius with an. After a car accident in his second year of elementary school, Takuma discovers that he is physically unable to forget anything he had seen, akin to. When he turned 10, he locks himself in his room in order to avoid having to endure another "memory collapse". In order to prevent it from happening, he unconsciously scratches his arms with his nails. One Sunday afternoon, Takuma attempts to commit suicide using a pair of scissors to cut open the blood vessels in his arms and is once again hospitalized. With every memory burned into his skull, he eventually he realizes that he is someone's child, not someone who had manifested out of thin air. He then sees a book lying next to him on his pillow, and he recovers miraculously with his memory collapses no longer recurring. Later on, Takuma realizes that this book reflected his own body, becoming scared after no one else sees it reappearing next to him. Eventually, Takuma decides to read this book, and finds that it contains all of his own memories in first-person.

In Rohan Kishibe's house, he and Koichi ponder upon the case of Hanae Orikasa. With no other details other than Hanae lived alone, Rohan concludes that she died due to a car accident inside her own home based on the crime scene images. He brings the cat Trinita out and uses Heaven's Door to read her memories. In it he finds out that Hanae suddenly dropped dead after meeting with a middle or high school boy at the window who had red scratch marks on both of his arms, with Hanae suddenly dropping dead.

Days later, on January 6, after Chiho looks for a book with Takuma in the Thorn Building, she brings up the mysterious death of Hanae Orikasa. After discussing it for a while, they go to Takuma's house which he was able to rent for cheap after a joint-suicide left body marks in it. At night, as he goes to sleep, he reflects on his murder of Hanae Orikasa, and how she was his father's former lover.
 * Chapter 2|

Dies irae
The book then centers back onto Akari Hirai. Teruhiko Oogami talks about how if Akari goes to the police, his life will be over. He threatens to kill her parents if she ruins his life, and then will go and proceed to take his own life. Akari refuses to eat anything Teruhiko gives her, and mentions that if she dies, he'll never get his 50 million yen back. After a day of being trapped in the alley, Teruhiko comes back and gives her a bag of supplies, including bottled water. Teruhiko says that to Akari's eyes, the bag is just full of yen, but to Teruhiko, it's a medal he gained after putting himself at extreme risk. Akari drinks Teruhiko's bottled water, and shortly finds out that the water was laced with a type of poison, presumably acid.

As Takuma is getting ready for school, he notices a TV report on how several apartment buildings in Morioh were rated much below the national standard for earthquake safety, yet they were all given a "pass" grade by inspection agencies. Takuma's life revolves around going to school, talking to some people regularly (on limited subjects), and spending time outside of school with Chiho. He realized that he could keep up appearances if he had at least one female friend, but keeps his other reasons of being around her hidden.

After he talks to his classmates a little bit, he spots Koichi Hirose talking to Josuke Higashikata and Okuyasu Nijimura. Using his ability to read lips, he fakes tying his shoes to key in on what they're talking about. After a bit of "listening", he knows that they are talking about the murder of Orikasa Hanae, and that they know about the scars on the arms. Takuma gets shoved by a delinquent, and falls on his chest. Crybaby's Boy pen falls out of his chest pocket, and as Okuyasu approaches to investigate, he accidentally breaks the fountain pen into smithereens. Josuke picks up the pen, and then returns it back to Takuma fixed, without any signs of breakage. Takuma planned to leave the school after the whole incident, but he decides to go meet up with the aforementioned delinquent, finding him in an empty stairwell. It's later revealed that he was most likely sent to the hospital with severe injuries from Takuma's stand.

Later, Takuma uses his "recorder" ability to play back Josuke fixing the fountain pen. He remembers seeing a "third arm" come out of Josuke, like it was a part of his soul. After a while of thinking about it, he concludes that it was one of Josuke's "mysterious powers". From this, he is able to conclude that both Okuyasu and Koichi both have these mysterious powers. Takuma meets up with Chiho, and they leave the school.

Koichi finds himself in class thinking about Trinita, and other miscellaneous things. After a short period of time, the temperature of the classroom started to rise dramatically. Everyone in the room starts feeling the heat and tries to open the windows in order to let the heat escape, but they find out that all of the lock in the windows have been jammed with hair. Due to the extreme heat, everyone starts taking off their jackets. Koichi doesn't notice anyone with red scratches on their arms, so he undoes Echoes' ability that was causing the room to heat up. At the same time, Yukako Yamagishi undoes her stand, Love Deluxe, which was jamming all of the locks in the room. They both leave the classroom together once class ends. This search continues for a week longer, until they finally encounter him.

Takuma and Chiho both walk around town, eventually reaching Morioh Station. Josuke Higashikata comes up and asks Takuma for the time. Takuma has a wristwatch, yet tells Josuke to go take the time from the train station. However, the clock has been broken, presumably by Crazy Diamond. Josuke gets a look at Takuma's wristwatch, but then tries to roll up his sleeve. After a bit of an awkward scuffle, Takuma's wristwatch falls to the bottom of the Morioh Station fountain. After Josuke tells Takuma to roll up his sleeve to get the watch from the bottom of the fountain, the mood grows dangerously tense. Takuma eventually just dips his hand into the fountain without rolling up his sleeve, which immediately prompts Josuke to call Okuyasu over. However, there are around 30 other boys at the school, each with red marks on their forearms, so they have to rule out Takuma for the time being.

Chiho and Takuma walk away from Morioh Station, and Chiho fixates on a line that sounded very similar to when she was saved from a delinquent at 12 years old. Chiho went back home, and as she sat in her room, she realizes a lot of things about Takuma. For example, his fixation on the Orikasa Hanae case was very suspicious, but Chiho decides to not say anything about it, wanting to preserve their current relationship.

Akari Hanae marks the seventh day that she had been stuck in the alley. She tries to accustom herself to her situation, but struggles with nature working against her. Eventually, Oogami Teruhiko gives her a pen and notepad, allowing Akari to communicate with him. He says that as soon as Akari will reveal the location of his 50 million yen, he would let her out of the alleyway. Oogami also talks about how he told her parents that she had gone out of town on a trip. She thinks of using the notepad paper to call for help, but can't find a way to get it out of the alleyway. Akari decides to not beg for her life, but get out with her freedom.

Takuma reflects on how he once got the flu. He has the memories of it consolidated into text, but would never look at that section of that book again. It was one of his "forbidden sections" where he stored all of his negative memories. Takuma then goes and calls Chiho over the phone, and they decide to meet up later. He decides to write a letter addressed to Josuke Higashikata, with a page from one of his forbidden sections enclosed. This stand ability only has a range of around 30 meters, but this was enough distance for him.

Since Takuma has a slight cold, Chiho decides to treat him to a nice Italian restaurant. This is Tonio Trussardi's restaurant, where there is a rumor that anyone who eats at this restaurant will have any ill symptoms removed from their body. This is due to his stand, Pearl Jam, which heals through food. As Chiho and Takuma enjoy their lunch, they both feel their bodies start to get a lot better. They continue to eat their lunch until it turns dark outside, and then they start to walk home.

As Chiho and Takuma walk home, they accidentally bump into a man talking on his cell phone. The man drops his cell phone, and gets enraged at Takuma for breaking it. After Takuma has the man "relive" one of his own punches, the man pulls out a knife. Takuma takes the knife, and makes several clean cuts, de-attaching several of the man's fingers, all to Chiho's witness. As they walk away, Chiho finally realizes that Takuma was the one who saved her from the delinquent 5 years ago, and finally stops trying to fool her. As Chiho embraces Takuma, he finally feels like he pushed one man into despair. Chiho's father is revealed to be Oogami Teruhiko, who had changed his name and got married 17 years earlier.

Josuke and his mother, Tomoko Higashikata, are at their house, when the front door bell rings. As Tomoko goes outside, she isn't met with anyone, but sees a letter at her feet, addressed to Josuke Higashikata. The envelope has no return address or stamp. Josuke is currently preoccupied with a video game, so he tells Tomoko to open the letter for him. After a weird silence, Josuke turns over to look at his mother, and finds an unconscious body with blood spewing out of gashes on her arms.

Akari Hirai reflects on a trip to Europe, where Teruhiko Oogami got cut by a disfigured arrowhead at a shop. Teruhiko got extremely sick, but eventually got better. She wakes back up in the alley, to Teruhiko throwing down more supplies to her. This cycle repeats until Akari reaches 50 lines on the wall, meaning it has been her 50th day in the alleyway. Akari then realizes that she has not used any of Teruhiko's menstrual sanitary products.
 * Chapter 3|

Confutatis
Koichi Hirose is in a second-hand bookstore with another classmate (most likely Toshikazu Hazamada). As they're in the bookstore, Koichi asks about the red marks on Hazamada's arms. He says that they were self-inflicted for some unknown reason, and then promptly falls unconscious when Rohan Kishibe walks into the room. After using Heaven's Door to read Hazamada, he finds out that a set of sentences has been written in someone else's handwriting. This set of sentences keeps talking about how Hazamada must keep scratching himself.

As they look for more clues on Hazamada, Koichi and Rohan discuss the Orikasa Hanae case even further. They also discuss Tomoko Higashikata's "suicide", who when questioned about what had happened to her, she says that she compulsively stabbed herself with scissors. Luckily, Josuke Higashikata's stand, Crazy Diamond, was able to heal his mother in a way that there would be no scars left. Koichi asks Rohan to erase the memory from her mind, which Rohan agrees to. They both leave the bookstore shortly after.

Akari decides to tell Oogami about the fact that she's pregnant with his child, but Oogami still leaves her in the alleyway. Oogami does throw a few books about pregnancy down, and Akari's mental wellbeing starts to worsen a bit. She considers a self-abortion, suicide, and other such matters, until the fetus inside her body started to move. She no longer felt as lonely as she once did, and Oogami started to allow her more items, like a gas stove to heat up water during the winter. After a few months of Akari's ordeal has passed, she encounters the same cat she saw when she was first in the alleyway. Akari puts her letter between the cat and its collar, and the cat leaves the alleyway.

Koichi and Okuyasu Nijimura are standing outside school, looking upon a heap of horribly deformed school desks and chairs. Okuyasu reveals that this is all of Josuke's handiwork, who has been extremely angry after the "suicide" of his mother. Koichi talks about how Rohan Kishibe discovered a clue about how the culprit would have seen "swings" and a "slide" through a window when he was younger. After a month of looking for the stated locations, with at least twenty parks in Morioh, there wasn't a single lead.

The school year comes and goes, with Okuyasu horribly failing his end of term exams. March 17, 2000 was the school's closing ceremony ending and Josuke and Koichi are walking to the bus terminal to head back home, due to the amount of snow making it unreasonable to walk. At this point, the book takes a small diversion to discuss Josuke's Savior. During this bus ride, they both spot a park, close to an orphanage. The duo get off at the next stop, and go to investigate the orphanage.

Chiho Futaba and Takuma Hasumi are going to Chiho's house to meet Chiho's father for dinner. Chiho's dad had previously told her to bring her boyfriend so he could meet her. When he enters the house, Takuma takes off his shoes as a courtesy. Chiho notes how both her boyfriend and her father have the same shoe size. Chiho's father walks to them, gets fake-angry at Takuma, after eventually chumming up with him. Takuma bows to her father and says that he hopes that they'll have a very long chat sometime soon.

Due to the Japanese New Year, Akari Hirai is in a very silent place. One day, a woman comes to speak to her from the roof of the building, and talks to Akari in the alley. The woman drops down a bundle of bills and says that if Akari lets her have half of the funds in the bag, she'll let her free. Akari realizes that her letter had stated that she had a large sum of Oogami Teruhiko's money, but not the exact amount. She catches onto one of the woman's statements: "Half should be enough to buy a nice house in Morioh". Due to this sentence, she figures out that this whole thing must be another one of Oogami's traps, because the woman came there already knowing the exact sum of money in the duffle bag.

As the woman returns with a rope ladder, Akari starts to climb up the ladder. She notices that there isn't a draft of wind as she rises in elevation. However, once she gets to a certain point, she realizes that she can't head all the way up to the roof. If she were to get to the top of the roof, she wouldn't be able to get away with her life. The reason for this is because the money was in the alleyway the whole time. On the night that she was pushed into the alleyway, she had tried to throw the bag of money across the gap between the two buildings in order to make the whole accusation process go a bit smoother, but she failed terribly and had it fall into the alleyway. She decides to keep going up the alleyway to lie and escape at some point, but Oogami comes and shines a flashlight at her face. After telling Akari and the woman that he could smell Akari's plan from a mile away, he threatens to cut the ladder if Akari doesn't descent down the rope ladder herself.

Scared for the baby, Akari's heart turns to lead as she descends the ladder step by step. The woman reveals that she was the real owner of the cat as she leaves, and reveals herself to be Orikasa Hanae. Orikasa also says that she married Oogami just recently. As the couple leave the roof, Akari is left in a shroud of darkness.

Josuke Higashikata and Koichi Hirose are in the orphanage, waiting to talk to the director of the orphanage. All of the kids are still looking at Josuke in awe, as he helped heal a girl's scraped hands on his way into the orphanage. Another thing they notice as they wait is that only the orphanage staff are allowed to give scissors out to the children. As the orphanage staff member walks back into the room to deposit the scissors back into a drawer, as well as sign it back in on a sheet, Josuke questions her about the strict security over a pair of scissors. The staff member retells the story of how a child stabbed both of their arms with scissors a few years ago. As they meet with the orphanage director, she asks if they are friends with Takuma Hasumi based on their questions about the car accident and the scissors. She doesn't divulge much more about him, but she states that the clock they came looking for was removed 7 years ago due to damage. Josuke and Koichi have finally narrowed down their suspect to one person: Takuma Hasumi.

A baby lays down on the ground as two adults stand over them. The woman talks about how the horse-shaped birthmark on the baby is the same as the man's. This is what Takuma Hasumi is reading about in his book. Baby Takuma remembers a very special golden brooch on the woman, upon which an older Takuma decides to act on. Takuma finds out that this brooch is hand-made, with only 10 of them ever being sold. Takuma eventually finds Orikasa Hanae through this method. He finds out that Orikasa Hanae met with a very secretive man once a year, and after overhearing their conversation, he is able to confirm that Orikasa Hanae was the woman who left him on the orphanage steps all those years ago.

On January 3, 2000, Takuma Hasumi calls Orikasa Hanae over to the window, telling her to come over and look at his own horse-shaped birthmark. Orikasa approaches him nervously, and only her cat is able to witness what happens. The true nature of Takuma Hasumi's stand is revealed, the exploitation of "Empathy". Although normal humans can not see The Book itself, they can perceive it, and can empathize with it. Due to this exploit of Empathy, the senses of the memory goes straight to the reader's consciousness. In Orikasa's case, she emphasizes by getting by a phantom of a car. The cat runs away from the scene, but Takuma's stand doesn't work on cats. The target must be able to read Japanese for them to empathize with it.

Takuma talks about how if Orikasa hadn't started to look for the baby she left on the steps all those years ago, she would have lived. It's assumed that Orikasa only started to look for Takuma due to the fact that she was rendered infertile due to a hysterectomy to get rid of a tumor. Regardless of the reason, Takuma doesn't care. It was a planned murder, and he left Orikasa in her home to bleed out to death.

As Takuma Hasumi is eating dinner with Chiho Futaba and Teruhiko Futaba (Teruhiko had changed his name before Chiho's birth), they are all having a pleasant conversation. As Chiho goes to her room to print out her manuscript of a book she was writing, Teruhiko and Takuma are both standing in the kitchen. Takuma had been to Teruhiko's house before, watching Chiho grow up, his sister from another mother. As Takuma walks around the house, he notes very expensive and lavish decorations while Teruhiko gushes about spending money on his daughter.

Takuma decides to consult his stand, The Book, to look up more information on Teruhiko. However, Teruhiko can truly perceive the notebook as being a notebook, and Takuma immediately starts questioning Teruhiko about "mysterious powers". Teruhiko talks about how fortunate he has been in his life, and starts talking about a bad situation he had at work. He reveals the nature of his stand's ability, the ability to isolate all human contact from a specific area. He says he hid something in this specific area, and no one else but him could approach it. After a while, he reveals that a "yapping dog" had been kept in the alley, and if anyone heard it "bark", he would lose his job.

After all of this information was told to him, Takuma makes the most out of time with Teruhiko. Takuma had been waiting for this moment for five years. After a short pause, Takuma tells Teruhiko he wants to ask for Chiho's hand in marriage. Right after however, Chiho's manuscript finishes printing, and Takuma says it was a joke. Takuma then leaves the house with Chiho, and after talking about her manuscript for a bit, Takuma decides to test to see if Chiho can see The Book. Chiho can not, meaning that she doesn't have any stand powers. Takuma gives Chiho a necklace made out of jet, and leaves. Takuma walks away, satisfied with what he has done. He didn't want to kill Teruhiko, not out of mercy for his father's life, but because he wants to make him live with what he has done.

As Chiho Futaba walks back into her house, Teruhiko Futaba tells her to not see Takuma Hasumi anymore. Teruhiko tells Chiho about his stand, "Memory of Jet", and then notices the Jet necklace around his daughter's neck. Saying "it's over…" are presumably his final words, as according to the Prologue to the book, Chiho Futaba would use a kitchen knife to fatally stab him in the chest and then burn their house down shortly after.
 * Chapter 4|

Lacrimosa
Akari Hirai is reflecting on her life. After the fake-escape incident, she wonders how life could have gone differently. She comes to the conclusion that her life has no meaning, but her child's life might. Akari decides that even if she has to give her own life away, she would do everything she could to ensure that her baby leaves this alleyway.

Josuke Higashikata and Koichi Hirose are leaving Takuma Hasumi's former orphanage, with the knowledge of where he lives. The duo decides to pay him a visit tomorrow, and part ways. While Koichi was away, Yukako Yamagishi had called him, so he decides to return the call. After talking about what he and Josuke had accomplished at the orphanage, Yukako brings up the fact that Chiho Futaba's house is currently on fire. Koichi decides to call Josuke, but his mother, Tomoko Higashikata responds that she doesn't know where Josuke is. Koichi realizes how much of a fool he was for believing Josuke would leave Takuma alone until tomorrow.

Koichi uses his cell phone to call Josuke's cell phone (they had gotten cell phones in autumn). Josuke replies saying that Takuma's house is empty, and he asks Koichi if he knows any other places were Takuma might be at this hour. Koichi mentions the Thorn Building, and then hangs up the phone. Koichi left his bike at school, so he must walk to the Thorn Building. As he heads out of his home, he wonder which one of his allies lives closest to the Thorn Building.

With an hour left until the Thorn Building closes, Takuma is reading Chiho's transcript. It's about a love story set in Morioh, but he wasn't intrigued by it. As he looks out of the window, he sees an unusually bright light in the section of Morioh where Chiho's house is. Knowing that his job was finally done, he decides to leave Morioh as soon as he possibly could. Takuma reflects on how he didn't have to use his three knives hidden in his jacket. Thanks to his stand ability, he was able to perfectly throw a knife. Takuma hears a loud smattering of footsteps on the first floor of the library but eventually disregards it for the amount of fire engines traveling outside the building.

As Takuma looks outside, his chair suddenly moved as if it was being pulled by an invisible thread. Okuyasu Nijimura identifies Takuma, and Takuma provokes Okuyasu to success. Takuma throws a knife at Okuyasu, but Okuyasu uses his stand, The Hand, to remove it from existence. Takuma plays the event back in his mind, as he tries to evade Okuyasu's attacks.

No matter how far away Takuma got away from Okuyasu, he would end up at the same spot he started at. As Takuma runs away from Okuyasu trying to penetrate his defenses, he decides to name his own stand. Much like Okuyasu's "The Hand", a simple name for such a strong ability, he names his stand "The Book". The more Takuma is pulled by The Hand, the closer he gets to realizing the scope of its ability and how to defeat it. After provoking Okuyasu by bringing up Keicho Nijimura, he launches his attack.

On a perfect line of sight, Takuma throws a knife directly at Okuyasu. Okuyasu easily scrapes away this knife, but suddenly, another knife accelerates towards him rapidly. Takuma had counted on The Hand's "deletion" effect, and threw the first knife as a decoy for the second. Okuyasu notices this second knife just as soon as it's too late to bring The Hand back to delete it. Instead of having it fatally puncture his heart, he leans into the traveling knife, resulting in a mere cut on Okuyasu's skin. As Okuyasu races towards Takuma for another attack, Takuma uses a fire extinguisher to make another escape.

Takuma realizes that although he had not consciously tried to do it, he had vastly underestimated Okuyasu. Takuma's final knife had fallen to the ground, which was impossible for him to get to at this stage. He realizes the only weapon still in his arsenal is The Book, which had the same range of effect as The Hand: 2 Meters. Throughout the fight, Okuyasu reveals that he already knows 2 weaknesses of The Book (Range and Non-instantaneous Effect), but not the third weakness. This third weakness the fact that the user must perceive the book to feel the effect of Empathy.

After Okuyasu attacks him again, Takuma notices that Okuyasu has his knife in his hands. Okuyasu throws the knife at him, but very poorly, allowing Takuma to retrieve it. Takuma uses The Book to retrieve a "forbidden section", and baits Okuyasu near to him. As Takuma faces it towards Okuyasu, he is met with a small surprise. Okuyasu has closed his eyes, negating the effects of The Book's Empathy. Takuma makes a hasty retreat, and rewinds the events of the last minute in his memory.

He realizes that he must rethink his plan as soon as he figures out that Okuyasu had intentionally thrown the knife poorly, and rethink Okuyasu as well. Okuyasu walks over to where he threw the knife, and uses The Hand on the bookcase where it was lodged. The bookcase falls on top of Takuma, nearly crushing him. As Okuyasu starts to gloat about his apparent victory with Takuma trapped underneath the bookcase, he starts to cough. Takuma has given Okuyasu the effects of the Spanish Flu (influenza), and with Okuyasu delirious with fever, Takuma is easily able to escape from the bookcase.

Because Okuyasu had toppled over the bookcase, a massive flurry of books had overturned on both sides. One of those books was The Book, perfectly positioned so that the forbidden section would directly face Okuyasu. Since Okuyasu wasn't being careful with his eyes around several books, he gazed upon The Book while looking for Takuma, and Okuyasu was immediately affected by it.

As Takuma walks away from Okuyasu, he gathers his belongings as Okuyasu attempts to curse him out through his drooling. Takuma tries to leave the Thorn Building, but Okuyasu has blocked off all forms of escape by warping all the door frames and bending the window bars. Takuma knows of a secret path up to the roof of the building, and uses that in hopes of escaping. Takuma is not bleeding, but he has a lot of "heat" in the areas he was damaged in after the fight.

Akari Hirai has been stuck in the alleyway for at least 10 months. She wakes up to a sensation of pain, and realizes that her water has broken. After an hour of extreme pain, she went back to a state of relative normalcy. She realizes that Teruhiko only came around at night anyways, and she comes to the realization that she must give birth soon as the time between the waves of labor pain grows shorter.

As Takuma slowly climbs the staircase up to the roof, he reflects on his sister, Chiho. Although he had every emotion in the world for her, he was never able to provide the emotion of love for her. He had faked it until the very end, while holding back his own feelings of guilt and nausea throughout. He reaches the top of the building, and looks all throughout Morioh from this vantage point. Takuma can pick out Chiho Futaba's house burning down, realizing that Teruhiko Futaba is certainly burning up right now. However, a voice starts talking right behind him.
 * Chapter 4.5|

 Josuke Higashikata talks about how he wasn't able to cure Okuyasu's symptoms, but called an ambulance for him. Takuma realizes that the largest mistake he had ever made in his life was fail to kill Josuke as he sees him standing right behind him. Josuke and Takuma trade words for a small amount of time, when Josuke summons his stand, Crazy Diamond, ready to fight. Josuke and Takuma are on opposite points of the roof, with a distance of at least 20 meters between the two of them. Josuke starts punching a wall right behind him, leaving extreme clouds of dust in the air. He then throws a large piece of rubble directly at Takuma, with it missing and landing at Takuma's feet. With Takuma shortly realizing that this could shortly turn fatal, he hides behind a spire for cover. As Takuma hides from Josuke, who knows exactly where he is, Takuma uses The Book to figure out Crazy Diamond's attacks on him. Takuma thinks that Josuke hasn't figured out as much as The Book as Okuyasu had during their fight, and decides to not make the same mistakes to finish the fight in one move. As Takuma thinks of his next move, the upper part of the spire is suddenly blown away by an extremely large piece of rubble which Crazy Diamond has just thrown. Takuma, realizing the deadliness of this situation, stuffs his mouth with snow to stop himself from talking into a grave. Josuke was also tracking the exhalations from Takuma's mouth, so having snow in his mouth would negate this effect. Takuma then jumps out from behind the spire and turns a forbidden section of the book to Josuke's face. Josuke, who already knows the conditions of activating The Book's empathy, has his eyes closed. Takuma quickly throws a knife towards Josuke's heart, but his aim is led astray as several of his bones suddenly break. The knife leaves a cut on Josuke's cheek. The first piece of rubble that Josuke had thrown at Takuma suddenly slammed into Takuma's back. Takuma is bleeding profusely with his insides extremely rattled. Josuke had used Crazy Diamond's restoration power to call a piece of rubble back to his location, angled so that it would strike Takuma in the back. Josuke reveals how he knew to close his eyes, which was because Okuyasu had gurgled "Don't Look" while stabbing his own eyes out with his own fingers. Okuyasu had lodged two fingers into his sockets, knowing perfectly well Josuke would heal him. Takuma notices that Josuke has not healed the cut on his cheek, and can deduce that Josuke can not use his own ability to heal himself. Takuma decides to tell a short story before he launches any counter attack, and that is of the tale of Josuke's hair. Takuma starts talking about Josuke's mysterious savior, and Takuma talks about how he could find Josuke's savior using his ability. He had memorized every high schooler's face by that point in time, and he convinces Josuke to let him open up the book to look for it. As Takuma feigns looking for the savior, he takes a break to insinuate that Josuke had saved himself that night. As Josuke relaxes for a moment out of confusion, Takuma throws Crybaby Boy's Fountain Pen at him. Josuke was able to smack the pen out of his way in time, with the ink in the pen splashing onto his face due to the amount of force. Josuke prevents the ink spray from getting into his eyes. As he immediately starts punching towards Takuma's, his eyelids accidentally slip open for a second, and he "empathizes" with Takuma's car accident. Takuma also quickly retrieves both suicide attempts and attempts them to Josuke, hoping to finish him off in the middle of his assault. Even though Josuke has been hit with enough pain to cause any human to double over in extreme pain, Crazy Diamond's fists finally connect with Takuma's cheek due to his intense self-determination. Takuma's teeth spill out all over the roof as well as blood pouring out of his mouth. Josuke says that either way, he doesn't really care about changing his life, saying that he's found nothing cooler than his hairstyle. The Book spills out a great number of pages, a large amount of his memories scattering into the wind like a flock of birds. With liquid drenching her thighs, Akari Hirai pushes with all of her strength on her abdominal muscles. As the cry echoes between the walls, to a very narrow strip of sky above it, a baby boy is born. When Takuma Hasumi was 12 years old, he went to the exact alleyway to collect his mother's body. He throws down the rope and descends into the alley. As he looks around the rotting books and cardboard, he finds white things scattered on the ground. He had left the alley with a black necklace as well as a postcard, and vows to take revenge on his father. Josuke Higashikata remains in the zone in which Takuma Hasumi can finish him off, yet Takuma's injuries left him unable to do a thing. Takuma realizes that he lost because he had just lived too long. Since he had too many memories, it took longer for the book to flip between the memories of his life. This time loss was the reason why Josuke was able to hit him before he could get the memory of suicide out. A pure test of speed is mutually agreed on, with the winner leaving with their life. Since a good chunk of Takuma's memories have disappeared, he is able to get to the fatal car accident page a lot faster. Josuke readies his punch and the race starts. However as Takuma turns to the page, he is met with all of his past memories. Beautiful memories from larger points play back in his mind and it slows down his turning of the pages. As he nears the car accident, Crazy Diamond's punch strikes him, shattering his ribcage. He loses his foot on the roof and falls off, with Josuke catching him. Takuma reflects on his very first memory, only one of a handful he could reflect on anyways. He reflects on the three days he spent near his mother in the alleyway, and he recalls his mother's wish for him. By instinct, he gained the ability to "not forget". Josuke has used up the last of his energy and is grasping on Takuma's left jacket sleeve as Takuma dangles off the side of the Thorn Building. The jacket starts to rip as Takuma reflects on why Josuke is saving his life. Above him, all he can see is whatever remains of The Book scattering across the town like snow. Although broken bones are poking through his skin, he musters any strength he has left to unbutton his jacket with his left hand. The last of his memories are him descending down the side of the Thorn Building, pulled by gravity. Eventually, all of his pages dissolved into the wind.
 * Final Chapter|

Communio
The child is born, and Akari Hirai doesn't mind the postpartum pain. She lets the baby suckle on her nipple for milk, and her heart is filled with delight at how adorable he is. One day, she places the baby in a basket, which is lifted out of the alleyway. In exchange for her baby getting to leave the alleyway, she will tell them exactly where the money has been kept. As soon as she sees the picture of the baby at the temple steps, she tells Teruhiko that the money was in the alleyway the entire time. Akari would lie in the alley, dreaming of her child until she died.

The fire that had broken out on March 17, 2000 died out after only one house burned down to ash. A man's corpse was found to be Teruhiko Futaba based on his dental records, but he was already dead before the fire started. Chiho Futaba was a primary suspect due to the fingerprints on the knife. Later that same day, the body of a boy was found face down by the entrance to the Thorn Building. The boy was identified as Takuma Hasumi who fell down the building after suffering multiple comminuted fractures. The director of the orphanage took charge of his body, and a service was held at a nearby temple. Chiho Futaba was not found ever since that night, and the close relationship between Chiho and Takuma was noted by the police.

At least, that's all the information available to the public. Koichi Hirose asks Josuke Higashikata and Okuyasu Nijimura for details while they are both recovering from their injuries in the hospital, and the story is pieced together. They piece together the story based on everything they've witnessed, but then move on with their lives.

As Koichi walks to study at the library with Yukako Yamagishi, he comes across Chiho Futaba at the bus station to go to S City. The two talk for a few minutes, where Chiho says that she was able to stay hidden from the police thanks to her mother. Koichi asks her for information on Takuma Hasumi, but she starts crying. All of a sudden, Koichi notices how large her belly is. Although the rest of her body is slender as every, her belly is round and swollen. Chiho says that she doesn't spite Takuma, rather she thinks that her baby gives meaning to his life, that Takuma's life wasn't a worthless speck of existence. She tells Koichi to give everyone her regards, and Koichi prays that both her and her baby's life remain joyful as leaves on the bus for S City. }}

History
In 2000, it was announced that Otsuichi would be writing a novel based on Part 4: Diamond is Unbreakable.

Titled JoJo's Bizarre Adventure - The Anatomy Lesson of Dr. Nicolaes Tulp (『ジョジョの奇妙な冒険 テュルプ博士の解剖学講義』), the story took place in Morioh a year after the events of Part 4 and featured several new original characters drawn by Araki.

An incomplete 30-page rough draft was released in a 2002 issue of Yomu Jump (a special novel-based issue of Weekly Shonen Jump) along with a full release date in February 2003, but the novel ended up proving difficult to complete. In the annual Japanese guidebook, Kono Mystery ga Sugoi 2004, Otsuichi claimed to have written over 2000 pages, but had thrown them all out. Intent on writing a novel that lived up to the manga, it took him until 2007 to complete it, which ended up becoming 4th Another Day.

Publication
A French translation of the novel published by Tonkam/Delcourt has been announced on January 24th, 2023. It is due for the end of 2023.