From what i get param and hwi are not in a committed relationship YET. So, i don't think ethically there is a problem with what param does (seriously, why call him a slut?). Would this situation break hwi's heart? Yes. But i think it's better for param to do it with mr. han before he actually commits to hwi so he'll have no curious temptations if he ever starts a serious relationship with someone
From what i get param and hwi are not in a committed relationship YET. So, i don't think ethically there is a problem with what param does (seriously, why call him a slut?). Would this situation break hwi's heart? Yes. But i think it's better for param to do it with mr. han before he actually commits to hwi so he'll have no curious temptations if he ever starts a serious relationship with someone