Responses
Since we've seen Bum and Sangwoo enough in their underwear I looked to see if they wore the same style. Looks like Bum wears briefs and Sangwoo wears boxers so they must not be sharing. It's gotta be the same pair.
I love how we're having a conversation about the character's underwear when there's so many other things to talk about lol.
Does Bum change his underwear? I think he only have one though... Σ(  ̄□ ̄||)