Cool de M na Kaichou to Kageki na Ama Icha Kozukuri Gakuen Seikatsu

The perfect chairwoman that everyone adores turns out to be a total masochist.
Go ahead and enjoy your sweety flirty and super stimulating academy sexlife with her!
Anytime, anyplace, your M slave & lover will serve you, her master! She's begging for it!!

Nagisa is a childhood friend of yours, slightly older than you.
She works as the academy chairwoman and you have had feelings for you for a long time.
But due to her overall excellence as a person, and a beautiful babe, you feel distance...

However, you are called to her birthday and there she gives you a confession.
A confession of love.
A confession that she is masochist.
A confession that she wants to be your sex slave!

[From DLsite English]