beta
So this is what I understood.
Ciel is originally from the 'medieval' world and the saint is originally from Korea with the power to switch worlds. She takes Ciel to Korea and he gets trapped there and marries our MC. Then they both die and somehow Ciel returns to the past before he goes to Korea and our MC was transmigrated into Ciels world as pink hair chick and they both remember their past lives. To our MC the world she transmigrated into is a world from a novel and to Ciel this is his OG world.
The saint is still from Korea but she isn't like Ciel and MC where she remembers her past life (I think).
And Ciel is trying to go back to Korea to find our MC, and our MC doesn't want anything to do with the current Ciel bc she thinks he is not the real Ciel but the novel Ciel.