Disclaimer: Figured it's been a while since I've written another chapter for this little crossover. So here's part 4!

Guest: Thanks!

ultima-owner: Thank you.

Katoptris12: Thanks!

StoriesUnleashed: We all love Dunkle Sans.

Guest (another one): I will!

"Speaking"

Frisk thinking

"Reading"

You know, it was hard to tell how long they have been down here. Could've been days or weeks by this point. Hard to tell when you're buried under a mountain.

Frisk climbed up the stairs in Hotland, and wiped the sweat from their brow. After their conversation with Dunkle Sans-the name made his day, they could tell-they fought a scary fish lady and made spaghetti with her, and befriended a socially awkward lizard lady. Alphys was cool though, in their opinion. They both shared a lot of interest in how things worked, and were smarter than they appeared.

Metatton… well, they could live without the TV with a wheel.

"hey, kiddo." Sans grinned at Frisk, seeing them finally arrive at the top of the stairs. "i heard you're going to the core." They nodded. "how about grabbing some dinner with me first?" Frisk's smiled brightly, and nodded again enthusiastically. "great. thanks for treating me." He brought an arm around Frisk, and guided them around the side of the hotel. "over here. i know a shortcut."

Not again. Frisk felt themselves vanish, before reappearing inside an almost empty restaurant. Letting of of the child, Sans moved to the other side of the table, and sat down in his seat. Following his example, Frisk sat down as well. "well, here we are. so, your journey's almost over, huh?"

It was. Frisk hadn't had this much fun in ages. Not since they still has their own parents. But that was so long ago now, it was but a memory. "It has been fun." Frisk wrote on the pad, showing it to the skeleton. "But I'll miss you guys when I go back."

"yeah, kid. i know the feeling." Sans wondered… if this kid didn't have a family like the Frisk from before, would they still be willing to be adopted by Toriel? Did they already have someone waiting for them on the surface? Sans though… he didn't want this Frisk to leave. It didn't seem as if they knew about the timelines, or the resets. In fact, they hadn't reset once since arriving here. It was like a blank slate. Frisk was innocent of the knowledge their old version knew, and he wanted to keep it that way. If he could, he wanted Frisk as his own.

"though…" Sans looked to the side. "maybe sometimes it's better to take what's given to you. down here you've already got food, drink, friends… is what you have to do… really worth it?" Frisk pondered his words, and shrugged. They hadn't harmed anyone, even if that was how the monsters viewed the human population. There was no wrong in what they were doing. Yet… they would miss everyone.

In fact, the only reason why they felt they had to return was because they had left in such a manner that they would have worried the people of the orphanage. That, and they felt guilty for making Mr. Pines worry, seeing them fall into the Bottomless Pit. When they got back, they were heading straight to him first and making up with him.

"ah, forget it. i'm rootin' for ya, kid. hey, let me tell you a story." Sans settled into his seat, feeling the warmth of the candlelight bounce off his skull. "so i'm a sentry in snowdin forest, right? i sit out there and watch for humans. it's kind of boring. fortunately, deep in the forest… there's this HUGE locked door."

"Toriel." They wrote. Sans nodded, pleased they were willing to respond.

"and it's perfect for practicing knock knock jokes. so one day, i'm knocking 'em out, like usual. i knock on the door and say 'knock knock'. and suddenly, from the other side… i hear a woman's voice. 'who is there'?" Frisk smothered a laugh, hearing him try to impersonate Toriel's voice. "i'm tryin' my best, kid. bear with me here. so, naturally, i respond: 'dishes'. 'dishes who'? 'dishes a very bad joke'," he winked. Frisk giggled again, and Sans chuckled himself.

"then she just howls with laughter. like it's the best joke she's heard in a hundred years. so i keep 'em coming, and she keeps laughing. she's the best audience i've ever had. then, after a dozen of 'em, SHE knocks and says… 'knock knock'! i say 'who's there'? 'old lady'! 'old lady who'? 'oh! i did not know you could yodel'!"

"Toriel was always full of bad jokes. You two must have gotten along well." They did. Besides Grillby, and Papyrus, Toriel was one of the few people he could really call a close friend.

"we kept telling each other jokes for hours. eventually, i had to leave. papyrus gets kind of cranky without his bedtime story. but she told me to come by again, and so i did. then i did again. and again. it's a thing now. telling bad jokes through the door. it rules."

Should he tell them about the promise? Sans looked to the side again, his mind a confused mess. They should know. If he didn't say something now, there would be a good chance they would figure it out on their own. "one day, though, i noticed she wasn't laughing very much. i asked her what was up. then she told me something strange. 'if a human ever comes through this door… could you please, please promise something? watch over them, and protect them, will you not'?"

Sans was their bony guardian angel. Frisk stared at him in shock. Had Toriel… made this promise for them specifically? Or was it… for the past humans who have fallen down here before them?

"now, i hate making promises. and this woman, I don't even know her that well." Can't say he didn't know her name. Frisk already got him to admit to that. "but… someone who sincerely likes bad jokes… had an integrity you can't say 'no' to."

"Sans? Was this promise for me? Or was it for other humans who fell before?"

"hehe, ah, guess you would've already pieced that together. it was after the second child had been… lost, when she told me this." He couldn't say killed. True, the kid probably already knew it, but it felt wrong to say it aloud. "do you get what i'm saying? that promise i made to her… you know what would have happened if she hadn't said anything? buddy…"

Letting his sockets go void, he gave them a hollow stare. "you'd be dead where you stand." Frisk gave him a deadpanned look, and shook their head. He'd never murder them. He was fooling with them at this point. They weren't scared in the slightest.

"... geez, kiddo. glad to know you can see right through me." Better than the last time he did this. Frisk had fallen out of their chair in shock. Another time they were close to tears. Now they couldn't care less. "i've done my job protecting you, right? you haven't been bothered by that weed since snowdin, huh?"

He did say he would keep them safe, when they felt so scared and threatened. "Sans. When I get out of here, I will break the barrier. I want to free you guys." Gravity Falls would be a perfect place for them all to stay in. They could even be the ambassador to help integrate them into society!

"i don't doubt it for a second, kid." Hopping off his chair, he walked towards the door. "well, that's all. take care of yourself, frisk. 'cause someone really cares about you." He walked out of the dining area, leaving a startled Frisk behind.

Since when had they… ever mentioned their name to Sans?

Wrote this under an hour. Figured I'd get something done with this story sooner or later.

Until next time!

Angel