"Aoyama-san?" Tomoko asked, tilting her head slightly to the side as Ryuuko made her explanation, eyeing the maid. All of that made... far too much sense to her, and explained the white dust in the library if it had come from the wall, and just why the barrier had broken when the thieves had never actually entered the library. As for the maid, Tomoko was well aware of the maid's usage of trick nails for weaponry, traps and various other purposes. But if she didn't remember...

Tomoko reached towards the awkwardly-shifting maid, brushing her bangs back. There was the black rune, seemingly written in ink. For a few moments she stared, then narrowed her eyes.

"This rune is designed to suppress and eventually destroy specific memories," she commented, "Which means that the thief must have..."

She paused for a moment, while the maid fretted over the fact that her mind had been messed with.

"... But you said the thief was an onmyouji? Runecraft is a mage's work."