There was a rustling at the window; the witch gestured in that direction until it opened enough for the familiar to wriggle in.
In wriggled a duck.
"You're not the usual... bird."
The waterfowl wagged it's tail eagerly; just because it wasn't a raven didn't mean it didn't want to be paid before delivery.
A handful of oats later, the witch read the message the duck had brought.
"Help. Captured by nixies."
That somewhat explained things.