Mixed feelings, MC wasn't so dumb to not notice the details about his girlfriend (Kana)'s behavior when they had their "first time" sex together (he quickly realized she wasn't a virgin), then didn't pretend it wasn't her the one on the videos (neither cried about it while jacking off and then keeping quiet about it) and confronted her, that was ok so far but he forgave her at the end, yeah, despite her cheating it still ended on a happy note with her going back to her boyfriend and moving away but this time with him aware of her sexuality and likely her new sexual urges after being toyed with and trained. Also, the yarichin and his buddies got arrested since he was so stupid as to stream on-line the orgy with Kana, and regarding her, well despite she was the victim of this she still got socially killed and had to drop school as she literally got ostracized and had no friends left beside MC, they moved away from their hometown to a city she's not known for her past deeds and she claims to want to stay with MC and she only needs him in her life.
Feel pretty much the same as Wilfriback. Mixed feelings. Things played out in a fairly realistic way, with stupidity actually resulting in the consequences that they should have.. Though I really can't believe or even respect that he forgave her after she knowingly and willingly betrayed him repeatedly while showing the bare minimum amount of remorse for doing so. I mean even before she was 'developed' fully the little slut had almost no problem taking the chad-kun cock bareback right out the gate, and then had the gall to keep having the MC, her actual lover, use rubbers. That alone would have been such a slap in the face to the MC, that even before taking in consideration that she later had a whole gang of douchy ntr bros run train on her raw, while blowing the MC off entirely. It's just not in the realm of reason for him to stay with her, let alone give up his own life, friends, and family to go move off to some far-off land for her sake, without even any guarantees she's not just going to go back to slutting herself out again behind his back after a month or so of living out there..
Man would have been wise to drop the hoe and cut his loses... at least thats how i see it.