Help!!

I'm looking for a manga about a boy and a girl who goes to the same school, and the boy always seems like a gloomy otaku guy in school but in reality, he has a tattoo and piercings and is acually a cool guy.

And the girls finds out about the real apperence of the boy (but I don't remember how she find that out but...yeah..) and the become friends or something.

Does anyone know which manga this is?? (=・ω・=)