Tooru Kouno's attractive appearance draws unexpected attention on his first day at an all-boys school. Having to transfer to a school without girls has been bad enough, but adding to his list of frustrations are boys staring at him all day long. However, he hopes that there may be girls around, since he ran into a lovely pink-haired girl on campus earlier that day. After being escorted to his dorm by his classmate, Yuujirou Shihoudani, he meets a student named Mikoto Yutaka, who looks eerily similar to the girl he saw previously. To his shock, he realizes Mikoto is the girl and confronts him about this revelation. Yuujirou divulges that he and Mikoto crossdress as part of their job: a school tradition in which attractive first years are chosen as idols called "Princesses" in order to boost the morale of the students—and because of his looks, Tooru has been chosen by the student council as their third Princess!