Hdhdjdj dude i was thinking this and just like it's so sad honestly. Like if this does happen i couldn't even blame the best friend becasue his only experience/knowledge about doors/being a door isn't a plesant one. Unlike Cain who took the time to explain and learned to be gentle, Sid is just... well Sid. He forced the best friend to do a lot of shit and drove him into wanting to die. That isn't at all plesant.
So as much as i don't want to see it, i wouldn't be able to blame him if he did believe that Cain and the MC have the same dynamic and him and Sid. I just hope everything works out :(((
(Sorry for the long comment!!! I hope this made some emblence of sesne and doesn't just sound like word vomit)
Hate to say this buttttt, it's about DAMN time someone told the best friend that Gyeong Joon is taken. Like, yeah I feel bad for him and all but it just hurt more seeing him think that he ACTUALLY had a chance while gyeong Joon was getting fucked by Cain. Like no hun, I'm sorry but Cain already worked his charm