Responses
I'm not sure but I kind of thought that when the ex told him to study and left, that was them breaking up... but you are correct, they never say anything about it until chapter 5. I hate cheating - this one doesn't bother me that much because I think of it as kinda a grey area
The summary says he was dumped right there, when his boyfriend said he was bad at sex, but yeah in the manga itself it looks weird.
They hadn’t actually broken up yet before the MC decided to enter the porn industry / date the other dude. All of the first four chapters, he never referred to his ex as his ex. They only truly became ex’s in chapter 5. Don’t get me wrong, it’s a funny story and you can definitely be a porn star and still be in a relationship, but if your partner tells you to watch a video and learn how to please them... watch it and learn how to please them. Don’t become a porn star without talking to them first, and don’t agree to date someone even through you’re still in a relationship.
TLDR: the infidelity turned me off