SPOILERSSS
Idk if black room ends on chapter 56 because to me it seems to. but the black room is full of mirrors and Jun finally goes into it. they then have sex (Yeon-Woo and Jun) and we finally know that Yeon-Woo's parents died of being murdered. I don't understand what the raws said so i don't know which one of them did it but i'm placing my bets on Jun. Apparently his parents show up in one of the mirrors in the black room with their body parts dismembered.