One word to describe "someone who made a pact"

I'm looking for the one-word equivalent to the german word "Paktierer".

"to do a deal with so."

In relation to making a deal with the devil / making a deal with a demon (or perhaps other similar entities). It would translate to: "A person who made a deal with the devil / a demon."

We use the term frequently while playing DSA (The Dark Eye, german RPG) and I always wondered about a good english equivalent. The word should be usable to describe a person: "Bob is a X".

Solution 1:

It's not quite the right fit, but a warlock is a practitioner of magic who gains their power from a pact with the devil.

Solution 2:

Since his name is arguably mostly associated with the pact he made with the devil, maybe 'Faust', 'Faustus', or uncapitalized 'faust', can serve as an obvious synonym for a person who made a deal with the devil, e.g. 'Bob is a faust'.