Aziraphale watches Melanie closely, trying to spot any sign of discomfort, but she seems only composed and perhaps curious. This is rather novel for her, he supposes.

And he can't deny that he is curious in turn. He's heard Melanie's story in pieces but never the whole of it; he senses there is some she's keeping from him, and he wonders if she'll tell Illyria any of that. Where he has deemed it impolite to ask directly, Illyria has no such filter. He feels a little guilty for thinking he might benefit from that trait, but it's not as if he arranged this. He's only a bystander.