It must be Itou-san!! But more than an anime, it needs a movie omg!!
Don't care if is animated or live, but it needs to have some quality to be a good reflect of the original work.
http://www.mangago.me/read-manga/itou_san_kuraka_sui/
If you're gonna read it beware, this is pretty dark.
Also, carefull with chp 7, is a serious dark shit (more if ......
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