Bro didn't hide he was fleeting lover and a playboy, he's not a green flag but he's not the same kind of monster as horse-face. The thing is, I and bunch of others REALLY like it when the playboy catches feelings and he's the one to hit the curve, in my humble opinion, that's the tastiest kind of drama, also I've seen a bunch of high-end dudes that are that same flavor of asshole and they go about life w/o regrets so potato beating him a good one it's gonna be a work of art (in case I'm misunderstood, I don't excuse his actions)
The issue is how this trope is gonna deliver, I hope it doesn't end up destroying both their characters and mingwa gives it a nice twist but that's something we can find out reading along