Responses
From what I see, we don't have a clue yet what Karam's preference is because it was never mentioned before. Either if he happens to only like Jaewon or if he was gay all along. He rejected Jaewon because of the possibility that he may haven't accepted yet that he's gay and is probably scared of that idea alone or scared of what society thinks, or maybe because of another reason entirely that the author would reveal soon but why else would he reject Jaewon when their feelings were mutual?
NAH BTCH YOU AINT WELCOME TO BOARD THE SHIP ANYMORE. YOU LOST THAT CHANCE WHEN YOU REJECTED HIM