Fishman

A fish-like bounty hunter, named "Fishman" in the credits, appears at the beginning of Episode VIII: Jack versus Mad Jack, inside a bar full of bounty hunters. He is voiced by Kevin Michael Richardson.

Biography
He taunts Jack, then slurps his tea and threatens to kill him before Jack strikes, knocking all of the bounty hunters inside the bar unconscious. However, in the shot where all the bounty hunters fall down, Fishman is conspicuously missing, perhaps insinuating that, like a fish, he slipped away at the last second.

It is unknown how the past Aku's destruction affected his existence.