I've been dating Chiharu for half a year now. She's a rich girl with almost no dating experience and doesn't even know what a sex friend is. One day, while I was walking with Chiharu, I met my playboy senior again. I couldn't let that senior get close to Chiharu. That's what I thought, but before I knew it, Chiharu had fallen into the clutches of the senior who was using his smooth talk to get close to her. And the innocent Chiharu started to change before my eyes...