Tamami Kobayashi
Tamami shows up in Diamond is Unbreakable as the main villain of Koichi's arc, though he doesn't stay that way for long. He's got a Stand called Boy II Man that he uses to blackmail Koichi early on, but after getting thoroughly humiliated, he basically becomes a minor ally to the group. He's the kind of character who learns his lesson the hard way—which in JoJo's means getting absolutely wrecked before turning a new leaf.
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