I want to find a doujin i read long ago when looking at my dad's laptop. Its about a White haired Guy that blackmails his music teacher into doing anything he wants to so he doesn't spread lewd pics or vídeos of her. He ends up abusing her daughter as well, and in the end, he spreads her vídeos anyway.
All i know beside this Basic synopsis, is that the name of the doujin is NOT "Teacher's Hell"