He doesn't know how to reject people, I think that's the main flaw with his character
Saying just "no" or avoiding the other girl would sufficiate. He is not a toddler.
Saying no is easy for some people, for major people pleasers it's not. I'm not justifying it, that's why I said it's his most major flaw. Also, saying "no" and avoiding the girl would not suffice because she is clearly a stalker
I do agree you for normal situations but knowing his personality he "chooses" to not take actions rather than he "cant" because he doesn't even give an effort for it. Also I wouldn't be thinking him as "people pleaser " rather he is a person that would talk mindlessly of something doesn't go on his way. He lives the way he likes and not particularly think about others. He is in superior position in relationships he is in , leading the way, not being led. But I am almost sure author will give him a sob story about "how he can not relate people and doesn't realize the heartaches he is causing" and justify his densness. Saw so many similar plot that I am sick of it tbh ╮(￣▽￣)╭
I mean.. If u two are “dating” why do u keep letting a girl flirt with u and be annoying AND make your “girlfriend” upset? Because he can clearly see her face whenever yura is around him