"So we kept going, telling jokes back and forth, back and forth each day, until one day she wasn't exactly cheerful. I asked her what was wrong, and what she had to say gave me quite a shock. "Promise an old lady like myself, would you?" What is it? I asked back. "If a human comes through here, watch over them, won't you?" "<br/><br/>Sans stopped for a moment then spoke once again. "Normally I'm not a fan of promises. But someone who laughs at bad jokes? Has an integrity you can't say no to."