Complex sentence: Katrina sees a cut on Montoya's arm and her vampire instinct takes over as she grabs it and bites him, but he uses a Zippo cigarette lighter to burn the wound clean.
Split into simpler sentences: Katrina sees a cut on Montoya's arm and her vampire instinct takes over as she grabs it and bites him. He then uses a Zippo cigarette lighter to burn the wound clean.