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Hello, I was reading one BL manga as one does and I remembered a manga about a guy that transmigrates into a manga where in which if you have sex then you go through bitching and they would have heart eyes, so the MC becomes roommates with I believe the second main lead of the manga which believes that the MC is trying to seduce him, but the MC has no idea of it.

Fellatio in the bathroom and a wild night of sex after clubbing? What more could anyone ask for? Wel...

I don’t remember the name, but it was about hunting demon like demon slayer, but was created before. What I remember is that the MC has long green hair that is tied in a pony tail and that his clothes have white, pink, and blue, does someone knows what is the name?