Why does trash come to the conclusion that the FL belongs to them after everything they di...

Poor cliche writing from female authors who obviously have been cheated on, due to South Korea cheating epidemic. That's why there are so many webtoons and kpop dramas like this. Where the Ex cheated, and then suddenly becomes obsessed with the FL when they get dumped by them. Instead of making the Ex accept the breakup and have them both go their separate ways amicably, the author turns these trash men into obsessive stalkers, making them their final villains, humiliating and defeating them. Because these authors are just vicariously living out their revenge fantasy through their fictional FL character. But that's just my guess.