the boy actually control the girl. tell her what to do, how to do and she is doing what he tells her.
he is very in love with her but it's hard for him show her that. it's difficult for him to admit it. he kind of gangster, everyone is afraid of him.
she is not leaving him because she is in love with him and believe that he will change.

romance, drama, a little comedy, school life and shoujo.
please not old art or manga with naked girls all over the place.

something like:
Haou Airen
honey honey drops.

OOKAMI SHOUJO TO KURO OUJI Didn't mean to capitalize, but I have a feeling this is what your looking for its pretty good as well.

Bokura no Koi wa Shi ni Itaru Yamai no You de spells Yandere boy all over, but then again, they don't date each other, he only monopolises her because of his twin brother, but he is totally in love with her, but he is in denial with his feelings because of his twin brother. You wonder why I mentioned twin brother twice, but that's the important part btw.

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I'm in idol hell T.T