"Good thing I don't like carrying anything," jokes the skeleton, except... yeah, he does hold grudges, much as he likes to tell himself he's got his reasons, that it could always be worse, at least he's not like those humans who go out there and actually kill people, right?

Right?

But Sans, he's read whatever he could get his hands on when he was a smaller bag of bones, never once heard of anything on Earth called a fire country. So, that answers that. Hell, for all he knows, the guy could actually be from some distant galaxy or a really distant future, long after the remnants of his 'current' society have succumbed to the inexorable tides of time and entropy. But that'd be too interesting.

He's probably just from another planet entirely.

(Hint: that's actually the most interesting option for Sans.)

"Born under the mountain, buddy." He would have said 'born and raised', but, uh. That'd be less than truthful. "Weren't too many of us that lived long enough to remember the War," or the sky the rest of them never saw. "The King and Queen, sure. Gerson, who's as old as dirt and as down to earth as they come. Guys like me?" He shrugs.

"But that don't mean much," he adds, eyeing Sasuke again. "I'm guessin' even a guy your age has seen his fair share of war."