A girl who already has a boyfriend but forced to marry an enemy. a boy who already has a girlfriend but forced to marry an enemy. whether they will be compatible partner or become hostile couples??

I liked him since the first time in the school. he is a namja adored by all yeolja, including teachers who are celibate. he always helped me. I think he likes me .. But he helps everyone with an open heart. apparently not the only one who helped me. how can I express this feeling?