Graven hid it well, but he was both immensely and slightly uncomfortable when she came to sit beside him. Seeing her turn the remainder of his water into ice was another shock, but once he was thankfully prepared for. "Well, I guess I'll have to get a new cup," he said, setting it down.
At her request, he paused to think. After a moment, he said, "I'm not sure there's much I can teach you. From what I've seen of your magic so far, it seems to be external. That is, you manipulate the world around you. My magic, animancy I call it, is very different. I manipulate the life energy found in all living things." He drew his dagger, not to threaten her, but simply to demonstrate. "You see, I can't even do most of my magic without a long, straight piece of metal to conduct the energy. I can do some basic healing on my own, but with this dagger I can do so much more."
"I can draw the life energy out of other living things, and bring it into myself. It extends my lifespan, and does a few other useful things. If it's a strong or magically talented person, I get a lot more energy." He smiled grimly. "That's where the rumors about me stealing souls comes from. If such a thing as a soul exists, I've never been able to find it, but I suppose draining a person of their life energy amounts to a similar thing. I can also gift this energy to others. That's what Orson and the rest are." He indicated his guards by the door. "They aren't zombies. I give them a new life, with no memory of their old one, and let them choose what to do. They can stay with me, or leave to live on their own back in Connlaoth. Most of them choose to stay with me."
"So you see, I doubt I could show you much about magic. Unless you have some kind of internal magic that affects yourself that you haven't shown me." Graven kicked himself mentally as he spoke. He was supposed to try and convince her to stay, not give her reasons to leave! She would probably be terrified by what his powers could do, or worried that he would try to drain her. He was a fool to think anyone would accept what he was.