Shuichi Nitori is a boy who wishes to be a girl, while Yoshino Takatsuki is the opposite, and they both like to cross-dress as the opposite sex. As the two begin their life as junior high school students, they reflect on the events of their elementary school days, during which Shuichi confessed to Yoshino, but was rejected because she was not ready for love yet. During the first day of class, Yoshino is impressed by a girl named Chizuru Sarashina who came into school with a boy's uniform, while another classmate Saori Chiba lashes out at another student for bringing up rumors of Shuichi and Yoshino dating. After a day of walking around the city in a girl's school uniform, Shuichi tries on a dress belonging to his sister, Maho, and runs away when she catches him wearing it and calls him gross. He runs into Yoshino, who cheers him up and makes up with him.
女の子になりたい男の子・二鳥修一と、男の子になりたい女の子・高槻よしの。
小学校で出会い、お互いの秘密を知った二人は、共通の悩みを相談し合えるかけがえの無い存在になっていた。そして、季節は春。中学校の入学式を迎え、着慣れない制服の感触に戸惑いながらも、新たな生活に期待と不安を募らせる二人だったが、ツメエリを着て登校してきた女の子・更科千鶴の姿に目を奪われて ——。