Chitsunai no Ibutsu -Remocon Vibe de Kyousei Meirei-

Private academy teacher Motoya Atagi has a certain hobby.
He likes to use vibrators on women until they're totally responsive to his whims.

His M.O. is to find her weakness and take advantage of her.

Take for instance Nanami Hino, an eager teacher's pet who trusts him.
Motoya uses that to slip her a roofie and film her masturbating.
Not only is Nanami exploited, she's painfully betrayed by the teacher she loved.

What's more, other students and teachers hep themselves to her, as Motoya cranks up the shame...

[From DLsite English]