Yuu Nikaidou 二階堂悠

Former staff of Easter Company. In order find the Embryo, he joined Seiyo Elementary and became in charge of Amu's class in the guise of a ditzy but kind-hearted teacher. His dream when he was a child was to become a robot engineer but when his mentor quit, because of his ailing wife, and his parents opposed the idea, he lost sight of his dream and became a twisted person. But he recovered with help from Amu and Suu. He resigned from Easter Company and officially become the teacher in charge of Amu's class. A running joke is that he calls Amu; Himamori meaning "leisure time".