
I saw someone else comment saying that maybe yuri doubts that the bil was completely honest with the sister, like they married fast and the bil was maybe in a relationship with the teacher just before soooo it may have some words story in there
I’m bad at explanation lmao I hope you understood what I was trying to say

Don't worry, I understood you The one who I don't get is Yuri lmao I mean- his reasons to question his sister's marriage are legit, and the only link Yuri has to get the truth is Sunwoo... But Yuri is not investigating the situation, he is harassing Sunwoo, someone who is suffering as well. Heck, Sunwoo's suffering and even his kindness annoy him because somehow Yuri sees him complicit in the situation when in reality he is not. Maybe Yuri is telling himself he is doing the right thing since his reasons to suspect about the marriage are good, but he is taking it personally and that's where he goes wrong.
Yuri needs to stop projecting himself into Sunwoo, it's not his problem. All the plot is literally something he has no voice or opportunity to act on. Yuri is frustrated because he knows it so he found in Sunwoo a place where he can liberate all those negative feelings. I don't believe for one second he is doing this to protect Heejo. Dude, stop-