In jinx the second wasn't really obsessed it was explained that when he sees a pretty guy he crush on them for a few weeks giving them everything. before getting bored and moving on to the next guy. Potato is the next guy but we all know this is gonna be the last guy. (I kinda ship them (I read too many black flag manhwa) too even if I feel bad for it I'm just hoping for a redemption arc)
Its your own choice to ship whoever you want, it ain't wrong since this is a fiction.
In jinx heesung isn't that obsessed with dan and he never said anything to potato like he's going to be a substitute for dan unlike this bastard
(Don't judge me but I I still kinda like shipping it though hahaha I've been wishing for it to just have a second couple with that new guy and just let the main couple have their happy ending they've been suffering and it just keep adding up)
Ngl I like heesung and potato more than the main couple.... I wonder why. Anyway, I didn't mean actually obsessed I meant in the way that heesung gave all his time to Dan and that he showered him with gifts and such to seduce Dan but easily move on to the next crush like always which is Potato. But yeah potato is everything but Dan's substitute. (I'm bad with words since I'm not a native English speaker so my bad if you didn't understood me the first time.)
(And yeah, ain't no way I'm judging you- psych! I don't want the main couple to have a good ending unless Dan give the ml a bad life, ruin his reputation before killing him. This is the only right answer, the ml don't deserve our poor Kim Dan )
Bruh I almost fucking ship it but then I remembered he's obsessed with je-oh fuck you just die pleaseeee