Bubble, Rock human, Ocean, I am a Rock, Chess,

Yotsuyu was born a nameless Rock Human. Although his youth is undisclosed, he managed to steal the identity of a young man named "Yotsuyu Yagiyama" and become an architect. He is said to have been one of Jobin Higashikata's friends in college.[21] Yotsuyu was hired to build the Higashikata Residence for Norisuke in 2010,[21] as well as the Higashikata Fruit Parlor's parlor[8] and the renovated Morioh Stadium. At the same time, he worked as Tamaki Damo's underling in the Locacaca Organization. At one point, Yotsuyu approached Jobin Higashikata to enlist him in the organization. At some point before the events of JoJolion, Yotsuyu informed Aisho Dainenjiyama of his girlfriend's betrayal, and it is implied that the two were at least acquainted with each another beforehand. On August 19, 2011, Yotsuyu, alongside Tamaki Damo, confronted Josefumi Kujo and Yoshikage Kira, who had stolen a Locacaca branch from the organization. After both escaped, Yotsuyu was ordered by Tamaki to conduct a search in order to corner the thieves. After witnessing the A. Phex Brothers' defeat by Josefumi, Yotsuyu was driven away by the approaching earthquake and tsunami.[22][a] JOJOLION BATTLE WITH THE HIGASHIKATAS

Yotsuyu promises to Tsurugi that they can cure his disease Learning about the duo's survival in an amnesiac man dubbed "Josuke", Yotsuyu decides to eliminate the latter. He meets Tsurugi Higashikata and, by feeding the Locacaca to a dog, succeeds in tricking the young boy into helping him lure Josuke out into the open. Yotsuyu Yagiyama later appears within the secret room below the Higashikata estate as Yasuho Hirose sleeps. He produces a transparent membrane from his eyes to suffocate her in an attempt to draw out Paisley Park and examine it. Once Paisley Park manifests, he uses his Stand to trap it in place and analyze its ability. Yotsuyu reveals that he is an architect scouting out interesting properties such as the secret room, and states his intention to eliminate Josuke. Yasuho, in a last-ditch attempt to free herself, manages to fold an origami of a bunch of bananas, which she successfully uses alongside Tsurugi's Paper Moon King to trip the architect. Yotsuyu falls onto shards of broken glass that Yasuho had tried to use earlier to cut the film on her face. In the confusion, the architect mysteriously disappears as Yasuho frees herself from the membrane. Later, Yotsuyu assaults Josuke and Norisuke as they attempt to gain access to the basement by touching Josuke's foot and activating his Stand. Large flower pots begin accelerating towards him as the architect watches from the entrance, surprised Josuke would return to the location just to die again. When the two manage to avoid the flower pot shards, Yotsuyu activates his Stand a second time, this time summoning chestnuts toward the duo. "I AM A ROCK"

Yotsuyu fights Josuke & Norisuke, and is eventually defeated When Josuke and Norisuke escape inside the cellar, Yotsuyu resorts to kidnapping Yasuho from inside the basement cellar and dragging her through a hidden fault in the roof caused by the earthquake. Josuke and Norisuke follow him by using the latter's King Nothing to track Yasuho's scent. Yotsuyu sets her down among rocks close to the shoreline and hides, intending to catch the two by surprise by blending into his surroundings. This ambush allows him to use his Stand a third time and attract liquid pesticide in containers toward Josuke, hoping for the containers to burst and allow the liquid to seep into his skin and poison him. Josuke's response is to encase Yotsuyu in a large soap bubble, intending to carry him off and drop him into the sea. However, Yotsuyu is able to attract several nearby rocks towards himself in order to pop the bubble and escape, thinking he has foiled Josuke's plan. Josuke then reveals that he was merely positioning Yotsuyu closer to the shore, allowing him to use his soap bubbles to push the architect into the sea. Josuke attempts to force information out of Yotsuyu while underwater, preventing him from surfacing by wrapping his body in nets Norisuke salvaged from the shoreline. However, Yotsuyu's Rock Human physiology causes his body to break down and die, having become incapable of skin respiration. As his body breaks apart, Josuke spots a mysterious fruit floating away from the architect's pocket and disappearing into the ocean current.

Using Yotsuyu's scent from Yasuho, Norisuke manages to find the architect in his rock form. Scratching the rock skin with a boulder, and seeing it bleed, Josuke and Norisuke are puzzled by Yotsuyu's true nature. Yotsuyu uses their momentary distraction from observing the canisters of pesticide converging toward Josuke, Yotsuyu appears before them and declares that he will obtain the Higashikata's wealth and that Josuke is checkmate before disappearing again when Soft & Wet punches him away. Knowing that Yotsuyu will use Yasuho against him, Josuke chooses to go on the offensive and foregoes defending himself against the canisters. Spotting Yotsuyu from the bleeding scratch, Josuke imprisons him in a bubble and begins to transport him to the coast. Yotsuyu reveals his Stand, I Am a Rock, and pops the bubble with converging rocks as the canisters of pesticide reach Josuke. Covered in pesticide, Josuke nonetheless pushes Yotsuyu off the cliff with him and both fall into the sea. Communicating underwater with his bubbles, Josuke envelops Yotsuyu who changed into his rock form to protect himself in several fishnets thrown by Norisuke at his request. Josuke gives Yotsuyu a choice, either revealing him who he is, or face lingering underwater forever in his rock form for fear of drowning. Enraged, Yotsuyu only reveals that he killed Josuke earlier and that Kira saved him. Attacking Josuke again, but beaten, Yotsuyu starts breaking down and dies, only saying that Josuke will be betrayed by the Higashikatas in his dying breath. At the same time Josuke spots a mysterious fruit sinking in the water from the architect's bag. Pulling Yotsuyu's remains off the water, Josuke and Norisuke inspects them, still baffled by Yotsuyu's rock physiology. In the bunker, Tsurugi sees his grandfather and Josuke come back with Yasuho and take her to the bedroom, and reveals that after investigating Yotsuyu, he couldn't find any address or bank account despite his qualifications as an architect, raising the question of where does Yotsuyu come from and how was he raised and educated. Tsurugi then asks if they have seen the cure for the disease, which first being denied its existence by Norisuke, is then confirmed by Josuke when he reveals that he saw a fruit sinking down the sea. Linking that fruit to a possible motive for his presence in Morioh, Josuke decides to investigate the fruit to uncover his past. In the bedroom, Yasuho discovers a piece of the mysterious fruit in her pocket, and goes back to sleep.