In a society where succubi and humans live side by side, Hayato Yui, a reserved otaku, has fallen for his classmate Emu Katou, a succubus near the top of their class's social ladder. He keeps telling himself that it isn't lust and that he has fallen for her as a person, without ever saying a word of it to her. Emu, just as reserved, secretly has feelings for Hayato too and wants nothing more than to close the distance between them.