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...
I wash my face in the bathwater 
that my sister just used,
Also wasche ich mir im Badewasser
meiner kleinen Schwester mein Gesicht,
Me lavo la cara con el agua
que mi hermana acaba de usar,
Me lavo la cara con el agua
que mi hermana acaba de usar,
Je me débarbouille
avec l’eau du bain de ma sœur,
Mi lavo la faccia con l'acqua del bagno
che ha appena usato mia sorella
Eu lavo meu rosto na água 
que minha irmã tomou banho,
Умывшись водой из ванны,
в которой купалась моя сестрёнка.