Some things are best left to cartoons - particularly topics like rape and sexual assault - where the only people that have to suffer through it are animated characters. In Private Sessions, Professor Saki is so dependent on maintaining her relationship with her unemployed art teacher boyfriend Mikami, that when he threatens to dump her, she agrees to do whatever it takes to keep him. So despite his past - which involves sexually assaulting a female student at his previous school - Saki gets him a job at her all-girl school.
With a whole new crop of targets, Mikami enlists Saki's help and starts having his way with the young students, whether they like it or not. Most of them have to be bound and gagged.