Responses
I mean judging by their very dramatic homophobic reaction in chapter 2, Hyeon-jin was probably not very happy that Chan had told other people that he was gay and confessed to him even though it wasn't actually meant to be a romantic confession. Also I think the issue with his heart is a very sensitive one, so he doesn't like other people to know about it.
Ty, I understand more now
Why was Hyeon mad BC Chan said he confessed?