I read the Pixiv version a while ago. But it's been a while so some details might be missing. Basically MC falls in love with a Gyaru who, shocker, turns out to be a slut who sleeps around. Eventually Gyaru does sleep with MC but with not much feelings for him but the twist is the nerdy MC basically bangs her several times and is pretty good at it that it surprise her and she starts to developing feelings for him for real but she doesn't admit it though. A whole bunch of drama does ensue and there is some NTR elements[but the MC doesn't tries to actively try cuck himself, he wants the girl for himself] but I don't recall it being the main focus and It's pretty much about too opposites, from different social groups, falling in love with of course a bunch of horny.
Edit: read
@Ochrolv post for specifics of the story. I imagine the serialize version will make some changes/add stuff but mostly will stay the same. I doubt the author will pull a fast one and give a typically hentai NTR ending.
