Time: Unknown
Location: The Caverns
The information Sans holds is the key to understanding what had happened down here. What happened to all of the residents of this place? Where did they all go?

Sans chuckled, shaking his head. "I'm only kidding." He winked. "Or am I?" He said soon after, chuckling a bit. It made me look at him in more fear than I already did, this alone earned a chuckle from him, and I sigh, getting back to another topic. "We can only go on for a few more hours. You slept the afternoon away." Sans said, as he looked around. "Man, you're lazier than I am." He chuckled slightly.

"Wait a second—!" I said, scoffing playfully as he chuckled slightly. "I almost froze to death! You expect me to not sleep?" I said. "Humans are designs to sleep for at least 8 hours a night! Maybe more!" I said, laughing slightly as his back was turned to me.

"Then just..." He said, turning around. "Don't freeze to death." He grinned, chuckling a bit. "It's simple, really." He said, messing with the soft soul of the cavern floors.

"You can't just...—!" I tried to say, sighing and rubbing my temples, closing my eyes. "You can't just not freeze to death. That's not how it works..." I said, huffing, trying not to crack a smile, unlike him, who was having the time of his life with this. With teasing me. Almost as if he switched back. Just like that?

"Why not?" He said. "It's what I did. I had no problem not freezing to death." He chuckled, walking forward, which caused me to follow him with another playful scoff. "Sounds like to me you're just being lazy." He chuckled. "Which, I'm one to talk, but still. With your whole determined self, I would have never expected a lazy side." He chuckled.

"But—!" I said, sighing. I was going to make my argument even further, carrying on his rather ridiculous conversation, however, we passed by the same, small, wooden station that smelled of condiments, and where the pretty, blue echoing flower resonated within the darkness of the caverns. It stood high and proud, as if it wasn't even close to dying, despite the lack of sunlight. "Hey. It's that flower!" I said, walking over to it, feeling it's soft petals.

This was where I met Sans. Even if he was switched to his other persona.
I hated saying that, because I didn't know if it really was a persona switch. Split personalities wouldn't remember the period of times when they switched, maybe if I asked him about when we met, it could give me a clue? "Isn't this where we officially met?" I asked him.

"Actually, I saw you in the woods of Snowdin. But you saw me for the first time here, yes." He replied. Damn. He wasn't a split personality. So what was he? "And that's an echo flower. It'll repeat any phrase you say back. The last one, at least." He chuckled, watching my starry eyes glitter at the amazing flower as it whispered 'The last one, at least' back to me, softly and quietly.

Sans started walking the other direction, and I followed, skipping slightly to catch up to him. "If that was Snowdin, then where are we?" I asked him, as he slowed his pace drastically to a casual, slow stride. A comfortable pace for my thin body. "I just decided to call it the caverns." I said, staring at the water that flowed along the side of the riverbed. "Because, well, it's a cave." I laughed slightly, sighing and looking up at the fake stars.

"We're In waterfall." He replied. Looking straight ahead, not glancing at me. "There are 5 regions of the underground. The ruins, Snowdin, waterfall, and Hotland. There is also the core, but that is apart of Hotland." He said, answering my questions. This also answered as to why the part of the mountain gets so cold and hot, because there was literally snow in part of the mountain. What could be in this 'Hotland'? Could it be the core of the earth?

"It's pretty here." I said, smiling genuinely for what seems like the first time in forever. He chuckled.

"It is, ain't it?" He said, as we passed another dustpile. "Any other questions? You seem like the type to never stop asking." He chuckled a bit.

"I do, actually." I said, excitedly, as we passed another dust pile. "Where are the rest of the skeletons?" I asked. "What happened here?" I hoped to get as much information out of him while he was stable as fast as possible, just in case he destabilizes again. I never know when the next chance will be. "Where is the rest of your species?" I asked, noticing that Sans had gone silent.

I looked down, only to see that he stopped, and I stopped abruptly to avoid hitting him in the back. He was looking at the ground, where a pile of white dust lied like the rest of them. He only chuckled, his chuckling turned into menacing laughter rather quickly, as he turned around swiftly. "Oh! What happened to the rest of the monsters?" He grinned, telling the story full of joy and happiness, like he had never been in such a good mood— but that smile was back. "I killed them." He grinned.

My eyes widened as he kicked the pile of dust that was resting on the ground into the air, like it was worth nothing. "Woshua.." He said, grinning, kicking another pile that was close by, "Aaron.." he said again. My eyes widened. "Moldsmal.." He said, grinning. Another pile that was kicked into the air. "Hey, what do humans turn into when they die?" He asked me, as my eyes widened when he turned around to look me in eyes with his resonating, purple left eye. "Do you want to find out, Papyrus?" He said, grinning, taking a step forward towards me.

"W—... wait!" I said, my eyes widening. Could it be true that he killed every single 'monster' that was down here? A massacre? A mass murder?

A genocide?

"H—Hold on!" I quivered, backing up as he took another step forward. He raised his hand, nothing was in it, but it glowed a bright cyan, as his finger did when I had almost passed out in the snow.

"You know what I enjoy most?" He grinned, sinisterly, flaring his purple eye, his insanity. "Papyrus, can you guess it?" He asked, laughing his crazed laughter. You would have never guessed that this Sans and the other Sans were the same person. The other one loved jokes, while this one was crazed with insanity. "I bet you can, Frisk." He said, taking another slow step forward towards me.

"N-No..." I said. "Hold on! I thought you were—!" I tried to talk, but my voice caught in my throat once more in fear of my own life. My fear of Sans was so irrational, as if he was really going to kill me this time, even though he's kept me alive all this time. He was capable of killing, maybe that's what scared me about him.

"It's scaring the shit out of people." He chuckled, turning around, tucking his hands inside his jacket pockets, and walking forward.

My heart stopped, and I just let my hand fall to my side, as my shaking deceased. "That asshole..." I whispered, smiling slightly, letting out a small stifle of laughter.

"I heard that." He said, a few yards in front of me. I could only wonder how in the world he could do that? It seemed impossible. "Let's camp here. It deems safe enough." He said.

"Safe enough?" I asked.

"Yeah. Everyone may look gone, but in reality, the true monster is lurking in the dark." He said. "Dangerous creatures roam the underground now that the monsters are gone. You can't run off on your own, or you risk your life." He said, almost too perfectly.

"So, are these dangerous creatures the things that killed your kind?" I asked, not wanting to spring up any bad memories. I knew one person wouldn't be capable of killing an entire species. "How dangerous are they?"

"It's more like an 'it'." He said. There was a moment of hesitation, and a slight chuckle that came from him once more, as he slid down the back of a smooth cave wall, and plopped down on the soft cushion of the soil. I followed him, maintaining a relatively good bit of distance in between us, "And yes. You could say that it was the reason why the monsters are gone." He said. "You have nothing to worry about though." He said. "You're sleeping in it's den."

Although I didn't quite understand what he meant, as he spoke in riddles, I figured I would figure it out in due time. He was the last of his species from all I knew and could figure out with the small tid bit of information he gave me.

But from the information I did get, one thing did seem possible. He could be reverted back to his normal self. With enough communication, I could potentially get him back to sane conditions, and maybe I could even work with him a bit to better understand his species more.

I was determined to figure this one out.

Slipping my head against the wall, I rolled it back, looking at Sans, who had both hands in his hoodie pockets, and his head was facing downward, hanging low. Soft snores came from him already. Looks like the skeleton can sleep.

I was determined to get out of here.

I rolled my head back, feeling the heaviness in my eyes. I was finally able to get a good rest in. Even though it felt like that was all I have been doing for a while now. I soon slipped into a soft slumber with questions springing about like a wildfire in my tiny head.

I was determined to bring back his sanity.