
ari does know haesoo at all and has not seen any evidence of mincheol mistreating haesoo the very few instances mincheol, ari, and haesoo have all interacted together is:
- when mincheol and ari were under an umbrella and haesoo say them. mincheol said she was just family and ari has no other reason to suspect otherwise
- haesoo showed up to mincheol’s work and then quickly took haesoo outside to argue but none of that took place where ari could see (there isn’t even confirmation ari witnessed that)
-haesoo walked in on them fucking in her house. however, ari immediately left so she never witnessed haesoo and mincheol fighting, once again.
so yeah, there’s no way ari would know how mincheol treated haesoo and even then ari would never know the extent that mincheol was mistreating haesoo.

Mincheol explained that he still had to live with his ex-wife because of financial issues. ari is dumb for this but she basically thought she could “save mincheol from his ex-wife” by letting him stay at her place for good. She has no reason to think he’ll ever get back with haesoo, hence their continued relationship. It’s really minshit being good at manipulating and ari being dumb but she genuinely doesn’t know that mincheol mistreated haesoo so that’s what i think reika was trying to clear up. it’s not her fault in the sense that she knew, it’s just her fault for being too naive (doesn’t mean she deserves to be mistreated too)
I'm sorry but why are we hating on ari again? I don't remember the poor girl ever doing anything bad? Like her only fault is being young and dumb? Or did she actually do something and I just forgot? Someone please explain. 'Cause please let this not be another case where just hate on the woman for the man's shitty actions.