StumblingtoSuccess
It started with the most clichéd beginning possible. Betrayed by his beloved girlfriend, Ntr'ed - and he will transmigrate. And after that, Let me guess, he will slowly but surely get stronger and build a big/pokemon harem to get rid of his insecurities. *Sigh* Dude, harem novels have become so commonplace because of you simple writers that it's no wonder people hate them so much.
Its unclear to me why she revealed the scam to him if it was working in the first place. it would be better if he went uninvited and caught her in this situation. makes more sense. He maybe knew the parents were out of town and finally worked up the courage to shoot his shot. also prob make more sense if only the boyfriend and his buff friends beat him up rather than everyone imo. Having everyone else apathetic is more realistic. Overall, it's not a bad start, I hope it's clear that it's not that "people are evil" but instead "he is a bad judge of character". Not gonna be super happy if he goes all edgelord.