Itsuki Hashima is a popular, young novelist. However, he is obsessed with little sisters and his works seem to always include little sisters, so there’s some difficulty coming up with a new series. One day, his younger step-brother Chihiro and his colleagues, Hayato Fuwa, Nayuta Kani, and fellow college student, Miyako Shirakawa show up at his apartment. They enjoy dinner, drinks, and a game. That night, Nayuta makes advances towards Itsuki, but...
But when Itsuki-senpai and I get married,
Aber wenn Itsuki-senpai und ich heiraten
würden, wärst du mein Schwager …
Pero cuando Itsuki-senpai
y yo nos casemos,
Pero cuando Itsuki-senpai
y yo nos casemos,
Mais si Itsuki m’épouse,
tu seras mon beau-frère.
Però, quando io e il senpai Itsuki ci sposeremo,
Mas quando eu me casar
 com o Itsuki-senpai,
Но ведь как только мы с Ицуки поженимся,