Jou

A worker asobot, but his mouth is never seen because he has it covered ninja style. Jou needs lots of water to survive or he could die. Goku himself said he is invincible when battling underwater. His weapon is called 'Feather Sword'. Later, like Goku, he collected 6 keys which can change his appearance and which can also change his weapon into 'Feather Blade'. Jou came back to past along with Goku and friends, since the bandit should never abandon each other.

(Source: Wikipedia)