A bit of both.

[ He looks thoughtful now as he goes back to preparing food for them. ]

I made a Bargain with a creature known as a Bloodsinger back in the day. It needed someone to be an extension of its will to feed itself, and I needed something that could give me the means to protect people that I cared about. Bloodsingers unlock the full potential of the human brain and body, and also have specific control over blood and metal.