so he knows she's a soul from a different world in that world's Raeliana body... and he's trying to kill the supposed heroine of the original story.
Why don't he kidnap/catch her instead and have the three of them sit down and talk/share info on what the blond and the original Raeliana did/know and how the MC's soul end up in the body?
but then again, shoujo/otome stories are rarely made with sound and rational logic in mind.... let's see if this is another of those....