Sans remembered the fights against Flowey.

The constant struggle of killing someone over and over again, trying to break their own determination before they could break yours. In the end, Sans did manage to overcome him and force the flower to stop killing, but now it seemed pointless. All that happened was that Frisk fell into the underground and started up yet another useless cycle, and in the end the people he was trying to protect ultimately betrayed him.

"You know what," Sans said, crossing his arms. "I believe I owe you an apology."

"Huh?" Flowey questioned.

"Isn't that what you came here for, to brag about how you were right the whole time?" He asked, sitting down across from the flower. "You were right about all of them, Flowey. About Alphys, about Papyrus, about them all."

"I... Wow, you finally figured out that you were the odd one out!" Flowey let out a few stray giggles, his mouth twisting into his usual creepy smile. "Congrats on finally finding out you were their tag along, not their friends. Also, happy birthday, trash bag."

"Well, I apologize for being ignorant back then," Sans said, "I should have known, I was an idiot."

"Glad that you finally came around," Flowey said, "I can't believe what I'm seeing now, though. What an... interesting new ''family'' you've found for yourself."

"I figured you probably would've left the underground eventually to spy on us, but I didn't think you'd be able to find me so quickly," Sans said.

"I first looked for you with your brother, since you always used to be by his side, but I couldn't find you." Flowey said, "So then I listened to their conversations, Papyrus talks too loud for his own good, and to think that I would out that you of all people had tried to kill him!"

"Things change, people change," Sans muttered.

"I never thought people would change, as once you get to know them, that's it. They never become different, never grow." Flowey and Sans both shared in the memories of the thousands of resets he did before. "But you, you've changed so much. Look at you now, inside of this mansion with a bunch of people with so much L.O.V.E! I would have never guessed it from you!"

"How did you find me, exactly?" Sans tilted his head with the question, trying to pinpoint where he went wrong.

"I simply listened to what they all talked about, and then went from there," Flowey said, "They're all too stupid to put the clues together. If you were with someone who killed, then I would have to wait for another victim, and just follow the killer to their hideout. It's rather easy when you're a small flower."

"Who did you follow?" Sans asked.

"Some kid with black hair, but I do enjoy his face, reminds me a bit of myself," Flowey said, grinning in a way that held a striking resemblance to Jeff's own smile. "But I can't believe what's actually here. So many killers, most of them not even human or monster! How did you end up here?"

"Well, basically what you predicted before," Sans said, "I was just the brother Papyrus and the others hung out with, and when we got to the surface, they started to ignore me. Long story short, they screwed me over and now I'm mad at them."

"Interesting, how did they screw you over?"

Sans laughed, flashing his magic eye light at the small yellow flower. "You and I both know there's no more resets anymore, I can kill you right here and you couldn't go back to try and get the information from me. Torture won't work when I'm stronger and you have no more tricks."

"It's fine, I got enough information from Papyrus to settle my curiosity," Flowey said, "He does tend to speak rather loudly, it really is a problem for him. If he doesn't learn to fix that, then he might find himself in more trouble."

"Papyrus does have a lot of weaknesses, you exploited them rather often," Sans said, "But you can do it again if you'd like, I don't care if he lives or dies anymore."

"No, he's valuable alive, he gives me information," Flowey said, "But how come you don't go and kill him yourself? We both know you're rather... difficult to defeat. Especially with those abilities of yours."

"I'd rather not," Sans said, "I have a new life I very much like, I don't want to see him ever again."

"You should kill him, it's quite fun," Flowey said.

"You of all people would know, you did it constantly."

It was an unusual feeling, sitting across from Flowey in this new situation. Before he had hated the flower, even despised him. Everytime he would see him Sans would find himself in a sour mood. He never understood why the flower would do what he did, it made no sense. But now...

Now it was different.

Now he could see where Flowey was coming from, what Flowey felt, why he killed and hurt people. In fact, Sans could even relate to the little weed, it was such an unusual feeling that it made Sans have to lean against the couch to regain his sense of the cushions behind him.

Maybe they were more alike than either would like to admit.

It wasn't like Sans was the only one who suffered from Frisk's resets, Flowey did as well. He was even the one who came to Sans to beg him to put a stop to the human after the first full genocide run, to do to the human as he did the flower. However, it didn't work out, their determination and L.O.V.E was too strong. Sans put up a good fight, he knew the human hated him the most during those runs, but their determination to settle their curiosity toppled over his own determination to save his world. Sans could almost feel the sting of the metal slicing into his chest, he could feel the painful burn as his blood stained his body, as if he was back in the golden judgement hall.

He could feel the knife's cold blade tearing through his bones, every aspect of his body in utter pain as his health bar was dragged down to 0. No, no, he didn't want to die!

"You remember it too, the kids knife, don't you?" Flowey choked out.

Sans wasn't the only one mentally broken from that single knife. At least when he killed Flowey, he made it quick, and he didn't kill Flowey nearly as much as Frisk did. The flower didn't just focus on genocide runs, he liked to find out everything about people. It did involve killing others, but Flowey was quick to give up once Sans would step in. Flowey then resorted to mind tricks on other monsters to try and settle his curiosity, but he let time continue, so Sans was fine with it. Frisk, however, repeated the same two days over and over again. They would do the exact same things in a row just because they could, not even Flowey was that cruel. When he grew bored, he moved on. When he killed, he could be defeated, he could get scared.

Frisk didn't give up, and even Sans fell to his knees before them. Frisk wasn't scared, the usual tricks that sent Flowey sprinting to the hills made them only want to kill more to find out what Sans was hiding. All they were was curious, and determined, willing to do anything just for a few answers. Sans gave them the key to his room as a way to hopefully make them stop the resets, but it only made the child more curious and determined. He thought that determination would never break, until Frisk finally decided to let monsters escape to the surface. Sans was unsure if they gave up their search for his past or not, as he never saw them that much, but it was unlikely. Frisk would never give up until they were satisfied, and even then they would continue past the boundaries. That's why Flowey hid in the underground, to stay away from Frisk. That's also why Sans made sure to burn all of the documents from the true lab about the previous doctor before he moved out, just in case Frisk went looking.

Flowey knew the limits and drew back. He didn't want to erase the world, he just wanted to explore it.

Frisk didn't care.

"I actually think you have more courage than me, to be completely honest," Sans said, a finger tracing the armrest of the couch. "You saw right through Frisk when they first fell underground, and you fought them, no matter what they did. You even warned me about them, not to mention how you warned me about everyone else. You might have killed people, but looking where I am now, I don't think I can judge you anymore. What you did in the underground... I can see how you were justified."

"Glad that we're on the same terms," Flowey said, "You and I have always been more similar, now so more than ever. That's why I came to warn you about something."

"You did?" Sans asked.

Flowey nodded. "Usually, I wouldn't be so generous with information unless I had a motive, but I can make an exception since you finally figured out who you really are."

"I don't think I found out who I am, I think I just figured out who I belong with, people like myself," Sans said.

"Either way, something funky happened at the lab," Flowey said, "I don't know what exactly, but something relating to you disappeared from the lab."

Flowey didn't know much about Sans, but what he did know was that Sans was somehow involved with the Royal Scientist at some point and that Sans had some involvement with certain machines, and that he was smart enough to use the machines. He also was aware that Sans tended to look over Alphys studies to make sure her math was correct.

"What is gone?"

"Just one file... about the previous Royal Scientist."

Another bit of information that Flowey was half aware on was the topic of the previous Royal Scientist. There was a document in the lab that Sans wanted to burn, to make sure Frisk couldn't get to it, but he couldn't because Alphys was studying from it.

It was Gaster's notes on determination.

"I don't know how, or why, but it's gone. I know you know something about it, and it was the reason I was created, but Alphys and Asgore didn't take it. And humans don't come down to the mountain, I don't know who took it or why. The door was still locked when I came in, since I like to keep it locked, but it's gone."

The file wouldn't describe how to implement determination into a monster safely, as Sans had made sure to burn those studies long ago, but still it was worrying if someone else had it. Alphys was the only person who knew about the information before, and after her experiments failed, she never wanted to touch it again. It detailed information on how determination in humans was strong, and how it let their souls persist after death.

If the humans got ahold of that, and started to experiment, it could start another war.

That should have made Sans freeze on the spot from fear. It should have, but it didn't. Instead, he found himself laughing at the idea of another war. As if he would be participating, it wasn't his fight. He was with his true family now, he could sit on the sidelines and just watch, if that ever happened. Either way, he knew the notes by heart, no one would be able to connect it to him, or figure out how to put determination into a monsters soul, it wouldn't affect him at all.

"I mean, who cares?" Sans said, "If it's the humans, let them do their research, we're both still pretty strong compared to them. And if it's a monster, then they won't be able to do much with it."

"What if it's not a human or a monster?" Flowey asked.

A Creepypasta.

Slenderman could teleport at will. Ben could glitch through screens. Masky could pick through locks.

They could get into the underground and steal documents no problem.

Did they know more about him than they were letting on?