Sans-Serif's jaw actually drops, and he stares at Duchess with wide eyesockets as she hops down off the throne. "wow...you're a lot older than me." He laughs a little, scratching at his skull, equal parts embarrassed and outright stunned. "i guess i should have mentioned that i meant 'months', not 'years'."

The sensation of her fur is incredibly ticklish, to the point that he has to fight not to break down in giggles. And the noise she's making might seem a little alarming on its own - he even looks to Frisk to make sure it isn't - but she doesn't seem like she's upset or in pain, so it's probably a good sound. He half-raises a hand, but hesitates. Sans-Serif is not unfamiliar with the idea of petting fluffy animals. He's just never had to do it, and he finds himself more than a little terrified of doing it wrong.

"...i don't have a mother." He remembers the book, and can't help but frown a little, troubled and sad at the memory. "not like everyone else does. but i have my brother. and i guess i kind of have a father, even if he isn't here. and that's all i need." The words are true, and saying them out loud does make him feel a bit better. And besides: "people here are really nice when i'm scared." Even people he hadn't even met before, like Ryoji.

"...i still get scared a lot."