For some reason I thought hyung had lots of experience before (⊙…⊙ )

Damn I didn't expect Hyung would have sex

He does. He's very very experienced. Someone kindly explained there was a mis-translation. When Jinhan says "So this is what the first time feels like", what he really meant to say is "So this is what doing it with a first-timer feels like", in the context that he's complaining his student is bad at sex.

Ohhhhhh i seeee