Lupus invis

Having said her piece, Increment turned and left without waiting for a reply.
As she watched her fellow maid leave, Sixth took out her pocket watch.
Fortunately, she still had some time. After freshening up, she should be just in time.
“All right, I’ll go grab some more stuff to eat while everyone’s focused on Shizu-chan!”
Fiore and Lumiere nodded at Sixth’s idea.
“Oh~ that’s a nice idea~su!”
The sudden answer from the side made the three maids gasp.
“Lu-Lupusregina-san!”
With hands clasped over her lurching heart, Sixth turned to face the source of the voice. There had been nobody there just a moment ago, but Lupusregina had appeared out of nowhere while everyone was distracted by Shizu and looking away. She sat sideways on a chair with her legs up on the table and even had a share of her own food.

[...]

“In the end, we should call him the absolutely strongest and most—”
“…There you are.”
The source of the calm voice was CZ. The assistant butler Eclair she had been holding under her arm had vanished to parts unknown.
“…Stop using [Invisibility] all the time.”
“Soz~ it’s a habit ~su.”

- Overlord; Vol 8; Side Story 2