Usually after some time or immediately, due to the shock of sudden transmigration/reincarnation, the new soul will get attached to the body’s old soul’s memories. Because her old self was treated in a way similar way as Cayena (I think), she’s very attached to her. I understand why you’re confused though since I actually forgot she even had a Korean past due to her being so much like Cayena. Just think of her being very emotionally attached. That’s the best way to make sense of it in my opinion. But I have never really seen a situation in which transmigration/reincarnation and time regression were used all at once. It tends to only be one out of the three. So yeah it’s pretty confusing sometimes. Don’t know if this helps tho (￣∇￣")
im so confused, can someone explain about this? the story explained that in previous life she's an office worker korean woman who possessed(?) the body of cayena, right? but why is she talking about novel cayena's experiences and memoties like she had experienced it firsthand?? because from the way she's talking, i thought cayena time regressed to correct her mistake in previous life or something instead of transmigrating from another world to this one