I won't knock the artist for her "idea" of character development because it's her story after all. But re-read the whole season after taking a break after episode 35 (which honestly broke my brain a bit). I'll explain why...
1) Character Traits and Personalities
Never once can I understand Jaekyung or Dan's choices and traits. I understand Jaekyung's past is a "mystery" for season 2 to discuss but I should be able to read something other then anger and aggression on his face. I like that he has a resting bitch face but not that it's his only emotion you can read. I hate that I can't tell if he's interested, annoyed, happy or content, or even curious. The only time we get a small sense of humanity is when he was drunk as a skunk.
Making Dan always grovel at everything Jaekyung did to him and still "fall" for him doesn't make any sense. Never once was he treated with a single grain of humanity.
That flashback he had when he finally leaves of that ONE TIME they played board games had me full on laugh out loud like that had to be the saddest thing I've ever seen...they shared nothing but Sex, forced sex, drunk sex, and drugged sex...but Board games are what made him realize Jae can be a "good" man.
2) The falling in love
It's not believable on both their parts: Dan shouldn't even fathom being around Jaekyung outside his Jinx and Jaekyung never once tried harder to be seen as human to Dan. I will say when I re-read it I can see a small glimpse of 'bothered' behind his eyes when he first looked at Dan but after that it just reads as mean and sexually driven.
Overall...Jae is not a "black" flag but never once does he try to be anything but a bad partner and asshole. Also I still say the author's choice to make his jealousy show as possessive and borderline rapey in that chapter with Heesung will always be the dumbest choice ever. That choice alone makes me hate Jae as a human being let alone boyfriend for Dan.
That's so messed up and the fact I'm not sure how if Dan ever finds out will he forgive that man is beyond me.
I guess season 2 will truly make of break it for me.