MC actually loves the hyung (refer to chapter 2) but decided to push him since the hyungs father discovered their relationship without telling the hyung the reason. I think the hyung became obsessive because of the MC's action.
Hmmm seme could of just simply try to woo him in tradition way like this and ask him to dinner etc I mean on first glance he's charming enough not to be rejected but i guess asking him to try new sex toys works too
I like their do dynamic