Makoto Fairfield

Mayuri's classmate and friend, Makoto is actually the demon Mefisto Ferce, Beaut's subordinate. Beaut ordered him to befriend Mayuri because of how friendless she was at school. Over time, the two do become very genuine friends, to the point that Beaut himself is jealous of their closeness. Makoto, having both a handsome human form and a devil's natural allure, is insanely popular among the girls, causing Mayuri all sorts of trouble.