That's the point.

[As long as they're not his tears, it's perfectly fine.]

Nah, not sure there's much I really need, you know? [It's the more polite way of saying he's not sure if there's anything that Cullen can offer him.] Could just call it an IOU, if you want, but it might not be wise to owe a demon a favour.

[A joke, mostly. He likes Cullen, he wouldn't call on him for something awful.]