So basically a few years back I was reading this manga but I never finished it. It was about this chick who has a boyfriend. Her boyfriend turns out to be very good friends with this model or singer or some kinda idol type. I remember he had white or silver hair.

Well the pop guy is jealous of his friends girlfriend so he exacts revenge and gets her into a situation where they have sex. Basically from then on he blackmails her into having sex with him or he'll tell her boyfriend or something.

Also her boyfriend ends up cheating on her too.

The last chapter I remember was a flashback of the idol rapist guy living in a dog house outside of his house... And there's someone who lives next door to him which I think is the female protagonist. She shows him kindness yada yada yada .
That's all I remember. Sorry for bad description but if ANYONE knows the name please help me out !!!

ALL I DO IS READ MANGA. HELP ME. I HAVE TO STUDY AND HAVE A SOCIAL LIFE.

First thing that came to my mind was Cross and Crime. Dunno if this is what your looking for?

The mangas never been fully translated but u can find the raws online.