"Not just at the kill." he told her wiping the remainder of her blood away from his hand. He was fairly sure Hal would be incapable of such a thing. It amused him though how good she tried to be when they both knew so completely that she was doomed to fail. Poor dear "It makes him a better person that you too my dear but lets not argue."
At his core, Lord Harry was a hedonist. Life was there for the taking of course, to control those less than him was a right. And Katherine who even Hal had known upon meeting would be so much fun for him, was now right here and entirely stuck. She'd never tell them and he knew it.
"So, you miss it, this, the blood. Perhaps not suffering the way Hal does, the way the attack dog does. But you miss it all the same don't you? Are you wondering if you could kill me if you were strong, well obviously I wouldn't need your blood. And of course you're important now aren't you. Your blood. Oh Katherine. You'd be so much safer with me." he told her brushing hair away from her face in almost a mockery of affection. He didn't know the meaning of the word.
"How long do you imagine I can play at being Hal then? Days, weeks, I might go a month just for kicks. Break the little ghosts heart. Do you know he can't touch her, not in any way either of them can really feel? Do you know how mind numbingly boring it is being inside watching them? Suffering their ridiculously chaste PG ridiculous love life? God, its dull. I should find someone better, now how is Lily Potter of late. I hear the other me, from the other world, I hear he was quite taken with her. And then of course there's you. There always was you."