Responses
It was in good way. But he would somehow tease them because it's amusing and may cause some misunderstanding or jealousy.
But rest assured he is not serious with any of the main couple.
If you read and observe carefully some chapters show that he already interested or in love with someone else. Not very obvious, but I read too many BL that sometimes I subtly could sense something.
Hopefully that's the case
While that smirk is hot asf, it gives me bad vibes. Bad as in psychotic bad vibes.
Ngl I've been having this feeling for a while, and was having my eyes on the oldest and the cutesy ones. Seems like the oldest is the one giving this feeling, huh...
Then again, dude could just be amused by what he's seeing (in a good way) so yeah idk... ╮(￣▽￣)╭