Jesper sucks in a breath at the mention of Mercy, but doesn't otherwise say a word while Wylan explains. He had been there once, enough to know it was bad enough on a good day and a straight-up nightmare when anything from Hell was at play. It sounded as though this was definitely one of the worst times to have gotten tied up in there.

It didn't surprise him at all that people were kidnapped, or that Mammon may have had a part to play (either in the orchestration itself or as the target of some kind of cruel retribution). But then there was the matter of Kaz and he had to ask--

"You went after him?" To know what he did either Kaz talked (unlikely), someone else did (a little more probable), or Wylan had the foolish whim to go in after Kaz himself (on-brand for their lot).