You do know not all gay men act or sound like girls right....?😀 Some can still consider themselves as gay and be masculine, and just cause they don't act a certain way like how other bl novels potray them to be doesn't mean they are not any less gay than other gay men.
But on the note I think youngwoo is gay for the soul fact he does mess with more guys than girls, but who knows.
And for Tj they did say in an early chapter he recently had a gf he broke up with so who knows what he might say he is.