Monty only shrugs, continued polite innocence at Loki's 'offense.' He's clearly not bothered enough to start too big a fuss. It's more an insult to Monty's intelligence if Loki thinks he's actually going to believe that, anyway.

"Oh, I shouldn't like you to disappear, my Lord," Monty returns. "I am a man of faith, though, I shall grant you that." In the blink of an eye, there's a glass of wine identical to the one that Loki's currently drinking sitting on the bar between them. There's no illusion here, if Loki can sense such things. Monty doesn't actually know what variety of win Loki was drinking, but he believes that it will be the same as what's in that glass. "One might say that belief in things that aren't wholly real is one of my particular talents."