"I'm not a fiend, but I'm also technically not just human. I'm what's called a half-Alv in the place I come from. The Alvs were a race of very advanced magical beings who fought a war against elves, dwarves and humans hundreds of years ago. They no longer exist, but there are those who seem human who carry their magical talents, like me."

Yes, there are a lot of implications below the surface there, but he doesn't have time to get into all of that.

(Especially since half-Alv is his character race, and he grew up human a reality over from all of that.)

"However, the magic of contracts is, as far as I can tell, a talent unique to me within that world. An evolution of the scribe's art that goes beyond binding legally into binding magically."