This is what I understand so far:
Sahyeon is the one who died and was possessed by the demidrake (same as Muyeon’s stepdad). It seems that Sahyeon’s parents thought he was cursed to die before the age of 30 (i’m not sure if the “curse” or illness was related to the demidrake or not) so they had another kid (Junui) pretend to be Sahyeon. After Sahyeon died and was possessed by the demidrake, Junui stole the sword and tried to kill him but only managed to stab him and died in the process. Junui was reincarnated into the body of the man that Muyeon tried to stab through the wall in this last chapter and he now had powers similar to the demidrake (fast healing), but isn’t a demidrake himself.

Guys im lost please dumb it down to me
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