[Papyrus watches as she quickly sweeps up that giggling under a cool expression again, but doesn't worry overly much. Between what he's experienced since waking on the beach and the undercurrent of forgotten memories, he's sure, some people don't like anyone to see them being happy or soft. Tsunderes happen, it's just a fact of life. Maybe that's all this was.]

Well-spotted! I forgot my disguise at home... So anybody who can see me, can see that.

[Which sounds a little dismissive, now that he says it. Whoops.]

Still, I'm always happy to know people better. I'm not just any talking walking skeleton! I'm Papyrus.