I agree tbh
I think it's also poor writing on the author's part. I've grown fond of this series, but it just seems like the author couldn't find a way to write without making Seungwoo braindead. Like I get it's easier to build something from scratch, but you'd think he would at least listen to the girl friend's advice seriously. Kind of a shame really.
I am wishing now to enter that webtoon and drag Seungwoo out of Joonho's sight, just for the sake of this safety. Good grief.
And that's a fact. Period.
Seungwoo is like the damsel in distress character that is, sorry for the word, pathetic. He always giving Joonho a motive so the guy expect that maybe, Seungwoo is available and it is okay to have some advantages. So much careless. He even consult to her girl friend but then again, he pursue it. For Pete's sake, you've been friend for that manipulative guy for almost a year yet you didn't observe his behavior. That's a freaking red flag.