I think cause once everything is out in the open, mincheol would come crawling back to her and be "recommitted" to her and she'll have to chose between them unlike how now, mincheol is still in the dark. once he finds out, he's gonna go all in and taeha x haesoo has been doing well but only while mincheol was playing around. taeha knows it will happen eventually and honestly it should have happened earlier but the only reason it didn't is because he blocked mincheol's # on her phone. people always going back to their ex's and seeing how mincheol will never be satisfied without haesoo, the guy she chased who treated her like dirt suddenly love bombing her and being like "I'd sell my organs for you" could make her waver. why he's pretending to be a loan shark, I have no clue tho. my guess is that he thought mincheol was so vain that as long as haesoo was footing his bills he wouldn't care. if mincheol had completely abandoned a haesoo who he believed was getting assaulted because of him, he would be out of her life forever. I think taeha is shaken cause he expected mincheol to be more careless with haesoo rather than the way he's acting and he knows if he felt mincheol's anger and possessiveness, haesoo will too and it might make her waver. personally, I don't see that happening but I get why taeha's bothered by it
I don’t really get why taeha is doing all this??? Why lure mincheol to the house? Na Haesoo clearly likes him and cards for him… but he’s purposely (but also without realising it?) drawing Mincheol back