Penguin Teacher is a teacher at "Pretty Top", literally a penguin. He is the best teacher in Pretty Top and was the first to give Aira and Rizumu lessons. Penguin Teacher usually gets furious when Aira calls him a stuffed animal which causes her to change her sentence mid-way. He sits on top of Yamada's shoulders and is very awkward in Aira, Rizumu and Mion's eyes. Throughout the series, Penguin Teacher acts strangely and tries to get his face in cameras and in TV shows. In Pretty Rhythm: Rainbow Live, it is also revealed that he was June's partner in the past, prior before the events of the series, before he left her and became the teacher in Pretty Top. In the final episode, he fell into the Mascot Hell as punishment given by Peacock.

(Source: Wikipedia)