He wouldn't flash coin to impress her. While it might gain a gasp or two, it was probably best that the small thing that prided herself on her ability to kill vampires and demons might get a little... over zealous over the prospect of pulling gold out of thin air. And Sweeney valued his life in tact and his head firmly on his shoulders.
Not that he thought such a small thing could be a threat to him. All he'd have to do was put a palm on her forehead, keep his arm extended and she'd be helpless against him. The prospect, like this conversation, was amusing.
"Course not, lass." For a few minutes he focused on his cigarette again, deciding his next course. "You are young, you hunt demons and other fantastical creatures you only have half an idea about. You know everything about them, I suppose. Silly for me to think, then, that you'd know the Tuatha."
Turning, he started to walk away from the bridge and further into the City. Mel was welcome to follow if she wanted. "There's a pot of gold, lass, but no fucken rainbow."