Complex sentence: When Jadis appears, asks Caspian for drop of blood to bring her back, however, Peter appears and pushes him away, but then he himself is enchanted by Jadis and is about to give her some of his blood.
Split into simpler sentences: When Jadis appears, she asks Caspian for a drop of blood to bring her back; however, Peter appears and pushes him away. Yet Peter himself is enchanted by Jadis and shows himself willing to give her some of his blood.