Kosuke and Sayuri have been dating for about a year. They get along well and have sex frequently, but lately it's started to feel a bit stale. One day, they visit the usual love hotel and use their accumulated points to enter a raffle. The prize? A "starter S&M set" of adult toys.

"Hey, we won this - be a shame not to use it, right?"

He nods at Sayuri's casual suggestion, and they decide to give the toys a try. And so begins their private journey into S&M play.

[Translated from the official site]