Excuse the momentary relief on Crowley's face- that wasn't what he was expecting. After he takes a second to adjust, he smiles slightly, looking down into his wine.
"I'm a Vice now, darling. I used to be an Angel. That's when I fell in love with him. Of course there were times after I Fell, that I was jealous- I wanted to tear him down to my level. But... I've wrecked a lot of beautiful things in my life. Other Angels, even. I don't think I could actually do it. Put him through what I went through,"
He knew, of course, this had to do with one of her priests. He couldn't pinpoint which, but he guessed it didn't matter much.