[There's a glimmer of recognition in Sans' eyes, betraying just how familiar he found the stranger. It's hard to fight the sensation of familiarity.]

H-heh... sure you didn't just lose your watch? [It comes out feeble, humor crumbling against the mounting unease at the back of his skull.] Hey, man, I'm sorry to ask you again, but... are you sure we don't know each other?