"Nana, I'm going to tie your hands today, so you'll be my slave." My childhood friend, Nana, is cute and innocent, and like a little sister to me. We've been good friends since we were little, so I've never been excited when I saw her panties... but recently, for some reason, I've been feeling the urge to make a mess of Nana. I want to make Nana's body squeak and squeak and make her say, "Master, please forgive me." Maybe I've gone crazy... Thinking this, I played SM games with Nana as a joke, and before I knew it, I was going crazy with the intense SM sex... [An innocent girl turns into a submissive masochist]