Pet Sounds's Stand
This Stand used by Pet Sounds, and shared with Kazuki Karaiya, is featured in the spin-off manga Crazy Diamond's Demonic Heartbreak and the light novel Crazy Heartbreakers. Its name is not revealed at all during the course of the story.
The Stand was originally a long range Stand fully belonging to the parrot Pet Sounds. Due to Pet Sounds's natural weak will as an animal, it was not able to fully employ the Stand's power. It is only after Karaiya gives Pet Sounds a piece of his earlobe that the Stand reaches its full potential, along with giving Karaiya control of the Stand's power for his own needs.
The Stand has the appearance of a mechanical bird, slightly larger than its user. The head is small, with tubes protruding from it, and a large ridge along the top. While its central body is unseen, it appears to have a thin torso with several appendages. These arms have several circular joints which connect to several circular reels. These reels can unfurl into long thin strips, similar to a tape dispenser.
The Stand's legs are also fully mechanical in appearance, with them starting from the center of one of the reels. These legs have other reels attached where a knee joint would be, connecting to large mechanical talons (similar to a large predatory bird).
Pet Sounds's Stand was originally only used to record memories. After Kazuki Karaiya linked his soul and mind with Pet Sounds, the Stand is able to utilize Pet Sounds's stored memories as a powerful long range ability to target specific targets or large groups of people.
When Pet Sounds repeats a sound or voice from its memory, its Stand forces its victims to relive and re-enact the events of that memory. Those under the Stand's thrall gain a strange dimpled texture over their eyes. The Stand also appears to make punched cards enter its victims' bodies to replay the sound from inside of them.
The Stand's power not only affects people who were present for the relived memories, such as Hol Horse when he aimed at DIO in 1989 with Emperor, but it can also affect people who were never present for the memory, such as Hiraoka reliving Wilson Phillips crashing his car, or Josuke reliving Pet Sounds's owner being murdered by DIO. The Stand's power can also extend to multiple people at a time, as Pet Sounds can force several pastry chefs to reenact the actions of women who sacrificed themselves to DIO. Pet Sounds can also negate the Stand's effects, causing its victim's actions to diverge from the memory, as it does when it stops mimicking DIO's voice during Hol Horse's memories of him preparing to shoot DIO, making it so that Hol Horse's finger is still ready to pull the trigger, unlike in his memory when he never got the chance. In certain situations, the trapped person can uniquely interact with the memory, such as when Ryoko is able to communicate with Kakyoin's soul when she is made to experience his time being trapped in a doll through the powers of Telence T. D'Arby's Stand Atum.
The only limiting factor to the Stand's ability is how far the sound travels. If someone cannot hear the Stand repeating the sound, they will not be forced to relive the past event. The closer Pet Sounds is to a victim however, the more realistic the memory being replayed will be; when Josuke relived the memory of DIO killing Pet Sounds's owner, he felt the same pain the owner did while dying.
A victim can escape the Stand's control by remembering a more vivid memory, such as Hol Horse remembering how he fled Cairo with Boingo while witnessing Kakyoin's final Emerald Splash; or a stronger emotion, such as Josuke breaking free after flying into a rage. Another way to escape the Stand's control is to cut blood flow to one's brain in order to shock one's self back to reality, as Josuke and Boingo experience when they choke themselves with rope. Another weakness is that if Pet Sounds cannot accurately reproduce a sound in its memory the Stand's ability fails, such as when Pet Sounds's beak is injured and its vocalizations are off-key.
After one breaks free from the illusions, the memories of their hallucinations fade away, suggested to be because memories from the past can't be kept in the present forever. For example, Josuke only remembers vague details from the illusions such as that he was gambling, but the rest is unclear to him.