so if I'm getting it right, the one who killed him is Ha Seonghan? and because he's also the one who brought him back?
Spoilers: ... . .. Yeah, he wanted to kill Muhyeok in the body of Han Jaemin but Hajeong intervened and died instead then he brought him back, presumably the same way he, himself, was brought back.
so if I'm getting it right, the one who killed him is Ha Seonghan? and because he's also the one who brought him back?