Molly was wandering aimlessly through the corridors of the Barge. There had... possibly... been another disaster with her attempt at a wakefulness potion, and she might have been letting her room air out again before attempting reentry. She didn't think the fumes were toxic, but it was better safe than sorry, and besides--Mouse wanted exercise.

She slowed to a stop as she approached Snape, frowning a little in his direction. She couldn't see him, of course, but illusions and veils were her specialty--and she nearly always knew when someone was trying to hold a veil around her.

And Mouse was looking intently in the same direction.

"Invisibility's a neat trick," she said, raising an eyebrow in the direction of the veiled person. "The first one I learned."

Molly blinked a few times as Snape started to appear. Interesting--that wasn't how veils worked for her. "Um. Kind of." Actually, it had been accidental, while she was trying to hide her definitely not parentally-approved wardrobe choices from her mother, but it had certainly seemed like a good reason at the time.

"Do you often lurk invisibly in hallways?"