由紀子～堕天使奪還～

I used to think the school I go to was calm and peaceful. But one day, I found out that my teacher Yukiko is the sex slave of a bunch of delinquent boys. In order to find a way to free her from her cruel fate, I befriended the delinquents.
Features a beautiful teacher at the mercy of complete strangers!

[From DLsite English]