Yeah, it would definitely have to be Sponsored Magic and Feeding Dependency.
Might even work it as a pay up front version of sponsored magic. I could see some entities demanding their payment first rather than allowing debt.
Actually the up-front model seems to be canon for DtB, in the sense that Contractors seem to be able to perform Remunerations before, during or after the use of their powers. Wei (the explosive blood guy) pays his remuneration at the same time as he uses his powers (surprised it doesn't turn into a feedback loop though) as does the teleporter Brita (her remuneration is to kiss people on the cheek. She can teleport people if she's touching them. 1 + 1 = 2)
Then there are the characters who were able to pay off their Remunerations permanently (in effect, paying the mortage on their powers in full) like the body-hopper whose original body died. Wonder how to model that? Probably with a change in Aspect
and Refresh.