Melanie hums in consideration. She doesn't think Illyria is lying, but she's still not sure the god-king plans on behaving herself.

"Then we should have an understanding, too," she says, quite reasonably. "You agree not to hurt Aziraphale, and I..." she pauses a moment, less than eager to make this offer, but fairly certain Illyria will like it, "I'll tell you about how I helped conquer the earth, before the rift took me."