Koibito Play

Okuno is a girl who is pleased only by BSDM.
One day she meets Saeki, a normal guy, and they fall in love.
Their love is normal but true, and maybe is the only way to forget all the bad and dangerous experiences of the past.
From Baka-Updates:
Okuno Ryouko and Saeki are quiet normal students. But only at the surface. At university, they both feel out of place; so, Okuno visits a S&M club after classes. Saeki happens to visit this club as well; rather than participating in the activities like Okuno, he is there to play music. When they both meet there, they seem somewhat attracted to each other. But will this attraction last, when they come to know about each other better? Will love be able to bloom?