The twin sisters who have opposite’s personality, Kaede and Suzu. Kaede is a whiner who can’t stop but complaining for a smallest thing, in another word, a tsundere. Suzu is known as a quiet girl in the school, but a quiet girl usually tends have many secret. But despite their difference in personality, they do share the same nature, a pervert. Kaede loves to masturbate while imagining her friend, Hayato who’s also happen to be her student council mate. Suzu noticed Kaede’s feelings toward Hayato. She plans to lure Kaede into her traps. Suzu invited Kaede and Hayato to gather in student council room after school ends. In the student council room, there was a suspicious box on the table. Kaede who was curious putting her hands in the box without hesitation, but her hands suddenly are all tied up.