I observe that jungwon is not much connected to his parents (not in a bad term) .i think his parents are very typical korean family who care for social status in society more than their son's happiness. And jungwon really likes jay. May be he knows that his parents will never accept them on the other side jay's parents are divorced and ( some where he said if he has a gf his mom will feel lonely) . Thats why he is not accepting jungwon . But i think jay's parents are open minded.they like eo and happy to be with eo (but not in a love rlsp) but also stressed about future.