Risotto

find out who the boss (Diavolo) and the boss's daughter (Trish) are

Bucciarati and his team that are the limit of Pansiana (they all have Stands):
Mista, Trish, Narancia, Abbacchio, Giorno, Fugo

He sells drugs and he's from the boarding house.

Risotto's Stand, Metallica, uses magnetism to shape blood into any form by manipulating the iron in hemoglobin. Specifically, he can create sharp and deadly objects like razor blades, nails, and scissors directly inside his enemies, as well as manipulate his own blood to create iron stitches for his wounds.

Some facts about the character:
Born in 1974 in Sicily.
When he was 14, his cousin was run over by a drunk driver. Even though the driver responsible for the accident was convicted, Risotto never forgave him—and four years later, at 18, he personally killed the driver.
At 21, he awakened his Stand and later became the leader of La Squadra Esecuzioni, one of the crews within the Italian mafia Passione.
The Risotto squad was involved in the elimination of politicians, American gangsters, and anyone else who posed a threat to the organization.
He has a calm and focused character, befitting the leader of La Squadra Esecuzioni.
He is willing to go to great lengths to uncover the Boss's identity and vows to avenge the deaths of his subordinates.
Avoids direct contact with the target, instead preferring to observe and analyze their actions in order to then deliver the decisive blow.

Appearance: A 28-year-old man with a tall, muscular build. He wears a black hood-like headdress from which hang several small metal trinkets bearing the letters that spell out his name. The headdress mostly covers his hair, revealing only a light fringe that reaches almost to his eyebrows. He is shirtless and dressed in a long, lapel-less black coat with straps that crisscross his chest and trousers with thick, horizontal black and white stripes, reminiscent of the striped pattern of bees.