Carissa beams at him.
...and looks at the contract, somewhat unhappily. It's just incredibly stupid, on principle, to sign something a devil wrote for you, after an amount of review that can plausibly happen now without destroying the mood. The fact she can't see anything wrong with it doesn't mean that much and the fact that there's the clause about no unpleasant surprises means - more, but not enough. However, they don't want to get Keltham the impression that one should treat Lrilatha's contracts as even potentially adversarial.
Well, what's going to happen to her is already only bounded by Asmodeus's unknowable will and the fact that apparently being tortured enough makes her short-term worse at her job.
She signs without any visible hesitation.