Kodomo no Jikan

Well other than them both being a hentai there are a few similarities. Saki and Yuzuki they are both the characters of the main focus in these stories. And they are both people who throughout the hentai they start to lose their normal mental states. It's like most mind breaks but here you can see a masochist coming from this mind break.And after they've changed by the end of the story it might leave you saying "What the f*** just happened?" 

Both have some good teasing and involve a shota. 

There is some force in both animes except one is more of hentai and the other is more of just echi. 

In both of them the "babysitter" is forced to have do naughty things with the children. 

Is a shota anime (boy love)!