Sans is used to this, at this point, and opens his mouth for her convenience in order to allow it to be over faster. As usual, there isn't much inside his head besides intangible networks of magical energy, forming an almost entirely etheric nervous system.

He casts a nervous glance over at Greg, though. Has the human given it away? He isn't sure. More than anything, the uncertainty of whether or not anyone else knows is what makes him feel anxious. His tail starts flicking back and forth, subconsciously showing off his apprehension.

"... Wait, Zecora," he starts, stumbling through his thoughts. "Some of those nightmares are bad news tonight. Gotta let the night shift know."