A creature from Puyopuyo, debuting in Puyopuyo Tetris. He has a round yellow body, a :> face, and sits on a cloud; he has two cube tetrominos on his head. O can only say pipi (or bibi in Japanese).
Trivia
He plays the part of Tee's companion in Puyopuyo Tetris 1 and 2.
Though he's male in English, he's genderless in the original Japanese.