Kaiba was hyper-aware of his surroundings in the quiet, so he definitely sensed that something was off, even if he didn't immediately recognize what it was. A shadow shifted. Was it a ghost?

"...what?"

He attempted to conjure a light to investigate. This spell went better than the first one, but only just, a gentle blue light floating at his side. And one of the shadows was definitely a lumpy shape. He sighed.

"That's one way to hide."