I feel like chulsoo has too much of an obsession with someone who just does not reciprocate at all. I get he did that out of love, but it was wrong, and the fact that she had a boyfriend when she started to experiment... it's just really messed up. she should have talked to her boyfriend and figured things out if she was that pent up.
I believe she had already started experimenting before she started dating Jiha. That's what was implied in the rumors in the flashback with the high school reunion.
I feel like chulsoo has too much of an obsession with someone who just does not reciprocate at all. I get he did that out of love, but it was wrong, and the fact that she had a boyfriend when she started to experiment... it's just really messed up. she should have talked to her boyfriend and figured things out if she was that pent up.