Man I didn't even realize most of that, thank you for telling about it!
Preach. You explained it so well.
I thought so too! I think this time, Yohan is the one who will help yuri to come to his sense and realize what he really felt. I read the raw and i can see yuri and yohan friendship is so much deeper than it seems. Just like yuri helped yohan in FYL, I think in FOS yohan will help yuri.....
wow !! you're so quick !! (and cute ahah) screenshots are coming soon, so look forward(｡◡｡)
Considering For Your Love, I think the reason for Yuri's behavior is layered and not as obvious as it seems.
In the prequel, Yuri has a good relationship with the Teacher. Yuri has always been a rude person and he is not friendly. From there we can deduce, he does not have many friends. So, Yuri must have liked the teacher to some extent. That is why when he saw him drunk, he begrudgingly helped him to get back home. Remember, this is Yuri. He is not the type to help people. Especially not when he was in the foul mood thanks to his Noona's marriage, but he did it anyway.
When he realised that there is more to the teacher's relationship with his brother in law, Yuri thought that his brother in law marriage might have been faked, and that his teacher is doing something terrible to his Noona. This part is fairly obvious, but what is not obvious is his response to the teacher's behavior.
The teacher looks kind and acts kind in front of others, so for Yuri, it is a major betrayal when he believed the teacher is capable of doing terrible things behind everyone's back, therefore he made the remark that the teacher is two-faced, the type of people Yuri most likely hate the most.
Yuri's terrible behavior can be stemmed into two things, one is he was protective of his Noona, the other is he felt betrayed over someone he used to like. Of course, none of this justified his action, as I believe the teacher did not do what Yuri believed that he did. It does not help that the teacher is too depressed to defend himself, and Yuri jumped to conclusion. But I think, Yuri is a fascinating character that is more than just a rude jerk. He is after all, the one who pushed Yohan into going after Moogyeong. The title Form of Sympathy might be a reference to Yuri's screwed up way of helping people.