Sophia smiled. "It probably wouldn't do any good. Why waste punch without proof, and I don't know what proof I could give."
That was an interesting response from the lady. She was clearly interested, interested enough to actively look herself at the table, not that she'd see anything there. She was also invested in it herself, having been affected by it. But although she herself might investigate further she clearly didn't want Sophia to. Despite Sophia at present knowing more about what was going on than the lady.
This didn't seem to fit. And she'd learned recently, and tonight, that the world was a stranger place than she'd believed. She'd try to remember the lady's voice and general shape, and hair colour. And observe her walk and bearing when she spotted her later. And if they crossed paths again, she'd be interested.
And then she'd add the details to the list of the other hundred or so mysteries she wanted to figure out. Probably never to even be thought of again after tonight unless she bumped into someone that reminded her of this lady.
"I'm afraid I must be getting back to work." Sophia turned away to pick up a new tray. And observe and probably intervene somewhere else.