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...
If only Chihiro-kun were his younger sister,
Wenn Chihiro-kun nur weiblich wäre, …
Si Chihiro-kun fuera su hermana,
Si Chihiro-kun fuera su hermana,
Si Chihiro avait été sa sœur,
Se Chihiro fosse stato una ragazza...
Se o Chihiro-kun fosse
 uma irmã mais nova,
А вот был бы Тихиро не братом, а сестрой,