Need a little help

So... There's this manwah I've been thinking about for a few days now, but I just can't remember what the name was and where I found it.
It's about a guy, I think a nerd who goes to university or something and is kind of unpopular? But a girl finds him interesting and invites him to some kind of meeting where it's all about sex, but the guy doesn't know that. At the meeting there are the guy, the girl who invited him, another guy and 2 other girls I think. At first he has a hard time with it or something, I think he is in love with the girl who invited him. Then the guy goes through a kind of exaggerated glowup and has an extremely large amount of muscles and is suddenly the crush of all women yk of the university and has sex with every girl. But it may also be that I am wrong with the last point and it has nothing to do with the manwah I am looking for, but actually I am sure that it is like that

The characters are all slutty and only think about sex, actually just porn

I've searched up and down everything on mangago, but can't find it, so please help me^^