from what i remember of the manga is that the girl is sad because she cant "o-face" like girls from hentai so the boyfriend puts her on a training program which trains her muscles and i think they mention kegel exercises so she can have a crazy orgasm and about after 1 month of training they have sex.
ive looked around a fair bit and couldnt find it so if anyone does know what it is then ty in advanced.
ive looked around a fair bit and couldnt find it so if anyone does know what it is then ty in advanced.