He is the mastermind behind the Locacaca Organization, using his Stand to act as the TG University Hospital's head doctor, Satoru Akefu. Alongside the Head Doctor, Tooru disguises himself as an ordinary part-time medical student at the hospital. Unrecognized within the field of modern technology and medicine, he strives to leave a mark behind because of his fear of not putting any accomplishments next to his name and eventually being forgotten, doing so by developing a revolutionary medicine through the New Locacaca with the goal of restructuring the balance of power in society.
He is eventually revealed to be a Rock Human and a Stand user, wielding the calamity-inducing Wonder of U, an automatic Stand which causes anyone who thinks of pursuing either the Stand itself or Tooru to endure a Calamity.
Tooru appears to be a slim man on the shorter side, being just slightly taller than Yasuho. He has curly hair styled in a very round afro on his head, with two swirls on either side. In later depictions, these swirls are two ends of the same line, rather than being separate. He has thick eyebrows which he often raises to show cluelessness or general happiness (usually around Yasuho).
He wears a dark vest over a sweatshirt, which has long sleeves patterned with triplets of thick black lines. On the right breast of the vest, there's a symbol for the letter "S" with a sun surrounding it. A similar yet smaller "S" can be located on the crotch area of his pants. On either shoulder of his sweatshirt are two teddy bears. His pants have a floral pattern on them, showing what appear to be grape vines and leaves.
During his first appearance, he wears a white laboratory coat. He is frequently seen with earphones on.
Tooru is a callous and an overly suspicious individual who directs the Locacaca Organization from the shadows. He uses a friendly charade as a means to disguise himself and drive away suspicion.
Like many Rock Humans, Tooru has grown to develop antisocial tendencies as a result of the first 17 years of his life being defined by solitude. While he's able to conduct himself personably and often behaves in a casual, upbeat manner, Tooru's authentic personality has an incredible sense of ruthlessness to it. This is best demonstrated by his particularly dangerous misfortune-based Stand ability, as well as his apparent apathy toward the suffering of Yasuho, who he had interacted on positive terms with just hours prior.
Tooru is extremely ambitious and knowledgeable in both technology and medicine. However, he has a history of feeling as though his youthful appearance serves as a roadblock in his ability to live up to his full potential. Notably, he attempted to pitch an innovative new idea to several prominent tech companies only to be dismissed as a result of his perceived age and presumed lack of experience. As he explains to Yasuho, this caused him a period of prolonged anxiety and frustration over the idea that his life was going by without any achievements to his name. However, it is unknown whether that story is true or not. Tooru's main project is the cultivation of the Locacaca and the creation of medicine in order to secure wealth and power. With his Locacaca Organization, Tooru set up a profitable scheme by healing the wealthy with the Locacaca. His research team worked towards advancing the Locacaca's properties, creating the Locacaca6251, and pursuing the new Locacaca. The new Locacaca presents a great opportunity for the group, as Tooru muses about the riches and the power he could secure by exploiting the new fruit's Equivalent Exchange.
Tooru has a somewhat unusual affection for Yasuho. It is shown that he met her when she was a little girl and she unwittingly helped him find someone to impersonate. Tooru talks about enjoying conversation with her, and hopes to meet again. Later, he developed a relationship with her as a teenager but seemingly split apart so Tooru could pursue his true goals. Upon his introduction, Tooru wished to rekindle his relationship with Yasuho. Having previously grown apart due to his aforementioned period of poor mental health, Tooru is not only friendly but also flirty with her. For instance, he doesn't hesitate to touch her in an intimate manner and isn't disturbed that Yasuho openly rejects his advances, being sure that she has feelings for him. He occasionally teases her too, openly reminding her of their experiences together. Tooru's affection results in his relative mercy towards Yasuho, as when she confronts him, Tooru takes the time to warn her about his powers and proposes that she walks away to stay safe. However this mercy doesn't go further than simple warnings, as he's willing to sacrifice Yasuho's body during an exchange to heal his own injuries.
As the leader of the Locacaca Organization, Tooru prefers to hide his true identity as the Head Doctor through the form of his disguised Stand: Satoru Akefu, while also playing a role as an ordinary part-time worker in TG University Hospital. This entire charade requires Tooru to act relatively normal, cheeky and altruistic to those around him in order to appear harmless yet believable, such as prompting to help Yasuho find Josuke to tell him to go to the 3rd floor of the Hospital, "helping" Josuke pinpoint where the Head Doctor was standing during a chase, and even promising Yasuho that he'll testify in behalf of Josuke after a sudden "accident" involving Josuke and a hospital patient. Tooru keeps going along with the act, until he realizes what Josuke, Yasuho, and Rai were trying to do, and opts to "coincidentally" bump into them multiple times in an attempt to slow them down and prevent them from getting to the Head Doctor. When the location of the New Locacaca is revealed, Tooru drops the charade completely. He goes on to be a consistently stoic and goal-oriented enemy, eliminating those who get in his way with little to no care about who it is he has to kill and how much destruction he'll cause in the process in order to secure the fruit and ensure the success of his goal for his own race.
Tooru is a cautious fighter who avoids risks, and prioritizes his safety above all else. He holds absolute confidence in his Stand's ability to defeat anyone. Tooru repeatedly warns his pursuers about its effects, and uses it's bizarre nature to goad enemies into activating it. However, after being injured by Josuke's bubbles he senses potential danger and decides to call back Wonder of U. Tooru's Stand is also equipped with a few rock insects. He unleashes Dododo De Dadada on Josuke and Mamezuku to attack and trick them into pursuing him. He soon after discharges Obladi Oblada to hold off Josuke and help his Stand escape the battle. Despite injury, Tooru can persevere and make quick decisions to put himself back at the advantage. When Josuke succeeds in landing his new-found ability, he consumes the new locacaca to perform an exchange on Yasuho to heal his injuries. Even when he's surrounded and deeply wounded, Tooru has the presence of mind to try and taunt Kaato Higashikata about her son to goad her into attacking him, although his ploy doesn't work as intended.
Due to his long life-cycle Tooru adapts a perspective on life based on memories and dreams. He compares himself to a rock on-top of others, being a witness to the dreams and memories of others long past. Tooru asserts that at the end of all things, these memories and dreams last forever. He projects this belief onto others, seen with him taunting Kaato about her own legacy of cruelty and the death of her son's dreams.
- Main article: Wonder of U
Tooru is a Rock Human, as well as the user of the Stand Wonder of U. Wonder of U is able to create illusions which can be sent after a specific target. It can disguise itself and take on the appearance of a human, allowing it to interact with non-stand users. It can also create projections of itself, which can travel quickly between locations by phasing into and appearing on transparent surfaces, such as windows or picture frames. Wonder of U's ability is automatic and can be activated on any person who has looked at its back in either an attempt to pursue it, or otherwise moves toward it.
While Wonder of U's ability is active, targets will experience various instances of conflict which seemingly play out in the most devastating way imaginable. These calamities often involve an affected person repeatedly colliding with objects in their environment, resulting in far greater injury than is possible under normal circumstances. The ability's trigger is sensitive, as Mitsuba simply questioning the presence of Satoru Akefu at the Higashikata House was enough to activate it. The range of the ability is unknown, but it appears to be extremely large, as Josuke and Mamezuku were affected despite being nowhere near Satoru Akefu's supposed whereabouts.
• Tech-Savvy: As a hospital employee, Tooru is inferred to be very knowledgeable when it comes to technological crafting and regenerative medicine, and has an innovative outlook in life that he takes sincere pride in. He once mentioned to Yasuho about the idea of a wireless electromagnetic induction that he came up with, a battery duct that lets phones and other devices charge without the need of using any sort of wires and electrical outlets, as electricity simply bounces off in the sky and in between two devices. He also invented the technologically advanced medicine, Locacaca 6251, alongside his subordinates within the research group of his own organization.
Tooru, like other Rock Humans, was abandoned by his mother as a newborn and left in the wilderness. He shortly after infiltrated a wasp nest to continue his physical development. Approximately 17 years later, he rapidly matured into his adult body, killing the wasp colony in the process. He made up his own name, as with other Rock Humans, however his last name is unknown, and it is unknown if he stole the identity of another human or not. He then travelled to Morioh and entered society undetected.
Some time in 1941, as Lucy Steel investigates a mysterious land in Morioh, she and Joseph Joestar are caught up by a Guard Rail attacking them. As they run away, Lucy spots Tooru in the distance planting a Locacaca in a pot, before walking away.
Roughly ten years before the events of JoJolion, Tooru meets a young Yasuho Hirose, who was a little girl at that time. Noticing how she used her Stand Paisley Park to search through her mother's phone, Tooru impresses her by scraping two rocks together to make a fire while assuaging her doubts about him. Tooru asks for a favor and tells her to help him find someone, stating that he doesn't know their name but that he knows they are an elderly with a medical license and that they live alone and are isolated from their family. Yasuho finds him a suitable person for his Stand to impersonate, Satoru Akefu. Tooru gives Yasuho the rocks to impress the other children at Yasuho's summer camp and disappears into the trees, wishing to meet Yasuho again after she'll have forgotten about him.
It can be inferred that he began impersonating Satoru Akefu with his Stand Wonder of U after that.
Tooru and Yasuho were revealed to have dated in High School, although it is unknown why Tooru decided to attend the institution. Yasuho never learned his last name in their time together. According to himself, Tooru created a device that could charge other electronic devices via electromagnetic induction and brought the idea to several companies like Apple, Huawei or Softbank. However they all rejected his idea because of his youth and inexperience. He then became a part-time worker at TG University Hospital at an undisclosed date.
Tooru, along with his colleague Wu Tomoki, attempt to meet with Poor Tom to retrieve the grafted Locacaca branch. They disguise as ambulance drivers and arrive at the Higashikata orchard. As Poor Tom approaches the ambulance that Wu and Tooru are in, he is suddenly struck down by a calamity because of his "pursuit" for Tooru, killing him instantly. While the two manage to grab the branch after leaving Poor Tom behind, they are tricked by Jobin and Tsurugi Higashikata into getting an ordinary pear branch instead. They realize it was someone else other than Josuke and Poor Tom who lit the orchard on fire and that the other party now has the real Locacaca branch.
Tooru encounters Yasuho during her confrontation with Wu Tomoki at TG University Hospital. He teases Yasuho about their previous relationship, but otherwise, the two are on good terms, as he is shown following through his promise to relay her message through to Josuke.
Afterward, Tooru repeatedly crosses paths with her as Yasuho follows Josuke and Rai across the hospital. Each time, he flirts with Yasuho and tries to remind her of their time together. He ultimately calls Yasuho and leaves a message declaring his love for her and says he wants to get together again. When Josuke gets into trouble after being accused of murdering a patient who died near him, Tooru reassures Yasuho as he promises to testify in favor of Josuke.
Tooru later meets Yasuho by the doorsteps of her house. After a speech about Tooru's aspirations and relationship regrets, Tooru asks her again to get back together but Yasuho is distracted by her investigation. Tooru offers his help and shows Yasuho a photograph of Satoru Akefu. Having seen the doctor's face, as well as confirming a link between him and Mitsuba, Yasuho decides to go to the Higashikata House.
Tooru doesn't accompany Yasuho but instead eats fast food for lunch. Yasuho calls him and asks him for help since she's injured at the Higashikata estate. Tooru says that he'll call an ambulance but Yasuho refuses, saying that she has a way to heal herself. Intrigued, Tooru departs for the Higashikata estate. Once there, Tooru ignores Yasuho's suffering and simply observes the estate from the surrounding forest while listening to music. When Satoru realizes Josuke's plan of "inviting" the head doctor to come to him, Tooru shows great intrigue at the sudden development.
Joshu comes out of the house with the Locacaca plant in his hands and Tooru retreats into the forest to remain unseen. Observing Joshu and Yasuho, Tooru decides to let Yasuho eat the fruit to confirm its power. Plus, he doesn't feel threatened by her. While hiding, Tooru makes some noise, and unwittingly allows Yasuho to realize that he's her enemy.
Yasuho confidently claims that he is the user of the calamity-causing Stand and a rock human. She dwells on their strange past together such as their first meeting when a young Yasuho was out with her troop. Tooru tells Yasuho that he appreciates her and has fond memories with her, warning her about the danger of her seeing him, since it would activate a calamity, killing her instantly. He then goes on explaining how the Higashikatas are already under this affect, as well as Rai and Josuke who he claims will die soon as well. Yasuho takes Joshu's phone and begins scrolling through the contacts. Tooru again warns her, asking for outsider assistance would count as a pursuit and lead her to be the first to die. Yasuho continues with her action and Tooru states that Yasuho has changed the order of death, meaning that she will die through calamity soon.
Tooru tells Yasuho that she is going to die next, but Yasuho doesn't listen to him and continues to talk with Kei Nijimura in order to find Josuke. Moments later, Tooru receives a wound to the head thanks to the combination of Soft & Wet's bubbles and Born This Way's wind power. Tooru realizes that there is indeed a hidden power in Soft & Wet's bubbles.
Wounded, Tooru thinks about the nature of the attack. Sure that the "flow of calamity" uses the logic of this world to return any pursuit back at his foes in the form of a calamity, he realizes that Josuke's bubbles contains something from out of this world that isn't subject to the world's logic. Seeing that Josuke is too dangerous, Tooru decides to make his Stand leave the hospital even though he wishes to finish off Josuke. Tooru also reveals himself and confronts Yasuho, asking her to hand him the new Locacaca to prevent the calamity that will kill Yasuho from destroying it. Joshu, who has regained his senses, stands up and threatens Tooru, who remains unimpressed. The three of them spot something falling from the sky towards them. Tooru guesses that it is the incoming calamity and thus grabs Yasuho to insist she gives her the pot. Joshu thus tries to attack Tooru, but a falling leaf cuts two of his fingers. Overcome with pain, Joshu trips on Yasuho, allowing Tooru to take the potted Locacaca. Tooru then says his farewell to Yasuho.
As Josuke keeps shooting bubbles at Wonder of U, Paisley Park suddenly transports one invisible bubble with it from the hospital to the house via the cell phone connection. The invisible bubble flies towards Tooru, disappearing and reappearing inside of his abdomen. This attack knocks away Tooru with the Locacaca pot and stops Wonder of U's calamity, saving Yasuho from the approaching plane panel that hits the Higashikata house instead. Josuke explains to Yasuho over the phone that the bubble from his shoulder cannot be controlled, but has an "invisible spin", and it was with Paisley Park's help that he was able to overcome the calamity using this profound ability. At the same time, Tooru gets back up and eats the remaining Locacaca fruit and runs towards Yasuho, bleeding out from his injury. Joshu attempts to stop him but a rain gutter strikes him on his head knocking him out. Tooru reaches Yasuho preparing to perform the exchange, but just in-time, Yasuho aims the phone at him and another invisible bubble shoots out piercing his chest and throat. Tooru is sent flying again, hitting a car and landing on the garage floor, he crawls towards the door in the garage where a mourning Kaato Higashikata stands. Tooru crawls on the ground bleeding profusely, looking straight ahead at Kaato and planning to use her anger to bring out his ability. She begins to explain her stew recipe, which was Jobin's favorite. Tooru grabs a nearby saw and slowly gets back up. He begins to monologue about rocks atop the coastal cliffs, the memories and dreams it experiences. He taunts Kaato about her son's dreams and desires, how they never came to fruition. He attempts to stab Kaato but gets caught up in her stand's ability Space Trucking, the cards pin Tooru down and Wonder of U appears floating outside the garage. However, Kaato has no real intention to harm and instead begins to explain her ability. Tooru's bewildered about her true motives and questions her goals. When Kaato begins to open her deck of cards he immediately notices something between them and begins to panic. He demands to know what's between her cards, and Kaato answers that it's her family's curse. The deck is open and between those cards is Tsurugi Higashikata suffering from the Rock Disease. Tsurugi makes contact with Tooru and the equivalent exchange begins, Kaato's intentions are revealed. She came to the garage to perform an exchange on Tooru to cure Tsurugi.
The process of the exchange begins, despite having eaten the Locacaca fruit first Tooru still succumbs to the equivalent exchange. Kaato reveals the crushed branches within her cards, and pours the sap into Tsurugi's mouth. Wonder of U attempts to attack Kaato but it begins to crumble alongside Tooru. In desperation he begins to plead, arguing that the fruit is divine providence and begging Kaato to stop. Kaato brushes away his pleas, determined to cure Tsurugi's illness and bear this sin. Tooru begins to crumble further begs Yasuho to stop Kaato by reminding her of their previous relationship. Yasuho doesn't act and continues to watch. In his last moments, Tooru hallucinates seeing a hornet and crumbles away. Despite his death however, the calamity still manages to injure Kaato and is capable of manifesting as Wonder of U in Norisuke's mouth but fortunately, Josuke Higashikata comes to the scene and eliminates Wonder of U with his newfound ability, blasting the Calamity to bits.
- “When you say the elevator's dirty, you pee yourself in there or something? Ya know, you used to get pretty soaking wet from my fingers back in the day.”
- “These hands of yours... they're really always from above, Yasuho... whenever I reach my hand out to you, you always instinctively put your hand on top of mine without saying a thing...”
- “Looks like we ran into each other at a good time. Seems like that's always the way with us...”
- “"Electricity flying into the sky". The idea of making a mechanism for electromagnetic induction that can charge something without an electrical outlet. I even filed a patent on it. Nobody had ever thought of it. Really, there's nothing out there that lets you charge something while it's in your pocket. But when I brought the idea to them, those companies all told me this. Except the Chinese company, they just laughed at me. "There are lots of people out there in the world thinking the same thing at the same time. That idea's just a step too late."”
- “To the direction of the Perseus constellation... to the relationship we had back when the moon and mercury were lined up... we were... happy.”
- “Actually, Yasuho-chan... Would you mind if I asked you something...? I want to 'help' you guys...”
- “It's Higashikata Josuke... Interesting. So he's not pursuing... He's inviting!”
- “The right path... Even if walked on by a saint who makes no mistakes... It is unavoidable that bad things will sometimes occur. That is "Calamity"”
- “While I don't know their name, I do know... (1) That they're elderly, (2) That they once had a license to practice medicine, (3) That they're currently in a nursing home, (4) That they're not close with their family, so they rarely if ever get people visiting them.”
- “What really matters is making sure I get my hands on that New Locacaca. I'll collect just that one pot. And then I will vanish from this place and from TG University. 'Safety first'. That is my goal, after all. Yasuho-chan... Give that 'New Locacaca' to me.”
- “Calamities make no distinction between right or wrong. Honestly, even I don't know what's going to happen to you. But the one thing that is certain is that you will die very soon.”
- “You, just sit down. Why don't you take a nap or just sit there bewildered in silence? And most of all, you'd better not be getting any ideas of coming towards me.”
- “Farewell... Yasuho... After everything ends, all will remain are dreams... and memories.”
- “Atop the coastal cliffs! There is a 'rock'... Atop some others rocks, Higashikata Kaato... What that 'rock' witnesses... Is only "dreams and memories". Memories of the landscape from those scenic cliffs... Clear skies, rainbows after storms... Mist... The beacons of lighthouses... Migratory birds and gulls... Glehnia plants... Only those dreams remain... "That which remains when it ends"... Defeat or victory mean nothing to that 'rock' on top of those cliffs.”
- “I know the rumors about your past. 15 years ago, you killed some obnoxious boy for your eldest son Jobin's sake. Even though you atoned for your crime in prison, your husband Norisuke still will not give you forgiveness. Even though you did it out of 'love'... So what sort of memories do you have left now? Only of 'cruelty'. None of the dreams Jobin held when he was alive were ever realized.”
- “Do... You understand... What you're doing...? The new Locacaca 'branch'... Is a 'natural law' of this world... That came about on this land from the series of overlapping coincidences of the wall eye faults from the earthquake, Kira Yoshikage's death... And stand abilities. That plant will never again appear on this earth... Search any of the southern islands, you'll never find one. It is "divine providence that has appeared for the sake of life on earth"! This perfect plant will be gone forever... Stop this! Stop destroying all the "branches"!”
- “P-Please, help me... Yasuho-Chan. I... Don't want to die... You're the only one... That can save me... Please... We've been friends ever since you were a child, haven't we...?”
- “I just... ... thought I saw... a hornet... ... Oh, I see... It was... a memory... of mine...”