What he says makes perfect sense to her. It's odd really. She'd never thought she'd understand Ivar but he was like so many people she's known in the past. He wasn't a bad person, not entirely, this was just what he believed in.

"Would it help if you offered some of my blood too? I don't mind giving it to you, as long as you don't take it all." It was her natural instinct to want to help and since he truly seemed to want to repent and to go as far as hurting himself... it made her want to help him.