Koichi Hirose

Standing well under average height at 157 cm, Koichi is a slight teenager who wears his school uniform exactly as issued and leans toward casual clothes otherwise. His light hair usually sits neatly combed back, though it springs into spikes whenever he gets worked up; at one point he crops it into a flat-top, only for the spikes to return during his clash with Yoshikage Kira.

Which color that hair takes changes with the medium, most often blond, blue, or silver. His Vento Aureo look swaps the jacket for a longer double-breasted coat with metal wristbands and the Roman numeral three marked on either side of the collar.

Friendly, polite, and easily flustered, Koichi undergoes some of the biggest growth of anyone in Diamond is Unbreakable, and the way his Stand keeps transforming mirrors that change. His gentle nature means he rarely wants to harm an opponent, sparing Yukako even after she tried to kill him and holding back against Giorno, yet anger flips him into someone abrasive and foul-mouthed.

He delights in small discoveries, warms to people quickly, and gets pushed around easily, whether by con artists or by Rohan Kishibe, whose manga Pink Dark Boy he adores. Heaven's Door pegs him as a coward who nonetheless finds nerve when it counts, and though he wrestles with fear, claustrophobia, and open panic, he keeps pressing forward.

Every fight leaves him more assertive, until the boy once bullied by upperclassmen taunts Kira at death's door. His blend of kindness and courage wins over nearly the entire cast, and after a rocky start he falls for Yukako's fierce personality.

Born prematurely in S City in 1984 and raised as an ordinary Morioh teenager, Koichi begins his first year at Budogaoka High by meeting Jotaro Kujo and Josuke Higashikata and learning of their powers. Keicho Nijimura soon shoots him with the Bow and Arrow, and he manifests Echoes, a Stand still sealed inside an egg.

Battles follow that push the Stand to evolve: he beats the swindler Tamami Kobayashi with Echoes ACT1, helps take down Toshikazu Hazamada, and defeats the smitten but dangerous Yukako with ACT2 before saving her life. He aids the fight against Akira Otoishi, is turned into a book by Rohan, then explores Ghost Girl's Alley with him and hears Reimi Sugimoto warn of a killer stalking the town.

As the hunt for Yoshikage Kira intensifies, Koichi develops Echoes ACT3 to halt Sheer Heart Attack, is nearly killed by Killer Queen, and survives to help corner Kira, multiplying the weight of his hand to block Bites the Dust just before an ambulance ends the murderer. Two years later, Jotaro sends him to Naples to collect a skin sample from Haruno Shiobana, with Rohan having written Italian fluency into him. There he meets Giorno Giovanna, helps him defeat Black Sabbath, and chooses to stay silent about him, sensing a Joestar-like decency.