Nice theory, it doesn't explain why sunkyung has been sending terrible luck to sera tho. She basically cursed her (for years). Sera being emotional and violent seems in response to nobody believing her and being constantly in pain more then being evil.
I just don't understand yet why others were affected too and how
I kinda think of it like a hocrux from HP. Sunbiatch is jealous of Sera and have a massive narcissistic inferiority complex so that checks out her reason. My theory is that Sunbiatch is receiving help from some outlier powers or a really powerful shaman to switch their fate. Kinda like what happen to a certain character in Heaven's Official Blessing.
oooooooohhh that sounds actually really interesting and plausible like if your theory is true, it kinda checks out some boxes on why there's a big change in character for Sera herself and corresponding events or reactions....
Ok guys hear me out, I dunno why but I feel like if soul swapping can happen in this universe I feel like maybe cld have happened to sunkyung and sera. Just throwing theories out here
Like if the original was a nice sera and a mean sunkyung, then like maybe they swapped places somewhere along the lines, but they don't recall their memories. So then like maybe they switched back but like og sera died and current FL is here?
Honestly the more I type this out the more it doesn't make sense but it's an interesting theory, no? (⊙…⊙ )
But seriously this manhwa is so damn toxic idk why i still read it ┑(￣Д ￣)┍