It seems to me that the author is lost.
Even going through various situations neither the protagonist nor the characters seem to change, learn or reflect. They are one-dimensional.
The story tries to be more erotic and adult but is afraid to take more steps and ends up having a mood of a child thinking about sex.
The protagonist for no reason, and giving no reason, seems to think that all these "women" clearly hitting on him are kidding and that they secretly hate him.
The more chapters advance, the more the story is lost and the less sense it makes. I'm giving up on this manga.