The twin sisters are an unlikely pair: the tsundere older sister Kaede and the naturally cool younger sister Suzu. One day, on his birthday, Hayato is sexually assaulted by Kaede and Suzu. Hayato was feeling uneasy when he was blindfolded in a room at a luxury hotel, but to his surprise, Kaede and Suzu appeared in their underwear! The two of them have offered to do some work for Hayato as a birthday present... The twin sisters, who are always the ones being dominated, will this time reverse the roles and satisfy their partner with a service-oriented play!? On his way home, Hayato is now expected to reciprocate because the sisters' birthdays are approaching. So, Hayato, who is always being bossed around by Suzu, devises a plan to give her a naughty punishment: the "Suzune Orgasm Revenge Plan"! While I was playing with a bundle of bells attached to the rooftop railing as a toy, Kaede suddenly couldn't hold back any longer and kissed me...!?