Sans stood just outside the cell, trying to stay still.

Waiting for instructions. From Chara.

Behind him, he could hear Gaster groaning as he woke up. He wasn't too horribly injured, but there was no way he was doing any more fighting.

Chara didn't speak for a long time. They stood there, seemingly very deeply absorbed in the task of digging dirt out from under their fingernails with the tip of their black knife.

Sans knew better than to say anything. Knew that the Corrupt lord would speak when they were good and ready to speak. Knew that asking questions unprompted would very well get him, or his family, killed.

So he stood there, and waited.

Gaster calmed down, fully awake. Sans could hear the quiet murmur of Papyrus's voice as he explained to Gaster what had happened in the last ten minutes.

Eventually, Chara did speak.

"Sans."

He looked at them.

"Sans, I want you to do something. I want you to do what I made you to do."

"You didn't make him," Gaster spat, "I did."

Chara gave him a dark look. Their expression relaxed after a moment, though, and they shrugged. "Fair enough. Sans, I want you to do what I modified you to do. If you do, then I won't hurt your family."

"will you let them go?" Sans asked quietly.

Chara frowned. "Don't push your luck, Sans. It's a really stupid thing to do."

Sans looked to the floor. "sorry."

Chara waved his apology off. "Do you want to know what I'd like you to do?"

Sans hesitated a moment, then sighed. "... no. but i guess i have to if i'm going to do it."

Chara smiled slightly. "So, I will tell you, then. I want you to, firstly, go destroy the Pure base in Waterfall."

Sans waited a moment. "... is- ...is that all...?"

Chara nodded. "For now."

"Don't, Sans. Don't do it."

Sans glanced over his shoulder at Gaster. He was sitting up, leaning against the back wall of the cell. Papyrus was sitting next to him, looking a bit scared.

Gaster looked furious.

Chara walked over to the glass wall of the cell. "You do realize that if he doesn't do it, then I'm going to-"

"please. please don't hurt them."

Chara rounded on Sans, a wicked gleam in their strangely suddenly dark eyes. "I'm not hurting them, Sans. You are. If you don't do what I tell you to, you'll be making me hurt them. And you brought them here. You brought your brother straight to me, and your dad came because of that. This is your fault."

"D O   N O T   P U T   T H E   B L A M E   F O R   T H I S  O N   M Y   S O N ." Chara turned back to Gaster, who was struggling to his feet. "This is   N O T   his fault. The blame rests squarely on your shoulders, Chara. You are the one who made him bring Papyrus. You are the one who Corrupted him. You are the one who controls the Corruption." Gaster was on his feet, now, and standing right at the glass wall. "So do not for even just one second try to guilt Sans into doing anything."

Chara's eyes were completely black, now, and they gazed coolly at Gaster. "If I didn't know any better, I'd say you wanted to die." They grinned. "I've half a mind to kill you now, except for the fact that if I kill you, I have just a little less leverage over Sans. Still, I can't let your insubordination go unpunished-"

"please! please, i'll do what you want! just don't hurt them!"

"Sans, no. As your father, I am telling you not to do anything this lunatic orders you to. We'll be fine."

Chara's grin twisted maniacally upwards. "No you won't! Not if he doesn't do what I want! Because, doctor, I plan to break you. I plan to rip you apart, shatter every bone in your body, twist every joint backwards! And then, I'll let you heal, and I'll do it again! What you call "pain" is nothing compared to what I'll do to you! And I'll keep doing it, again and again and again, until this room becomes your entire world, until you forget anything else exists, until every waking second of your day is filled either with your screams, or Papyrus's, until you beg for my mercy! Until Sans begs for my mercy! And you know? I don't have mercy." They turned back to Sans, who was thoroughly horrified, and smiled blankly at him. "So I recommend you don't get yourself into a position where you're begging for my mercy, because you won't get it. Ever."

Sans tried to talk. Had he been able to move his jaw, it would have been opening and closing like a fish's mouth, as he desperately tried to talk.

But no words came.

Eventually, he hung his head, and turned to the door. "i- ... i'm going to waterfall."

And with his hand, he signed to Papyrus and Gaster. "love you. sorry."

And then he was gone, the door closing behind him.

Slowly, Chara turned back to Gaster. Their eyes were still completely black. They smiled, and a dribble of pure blackness slipped out of their mouth, trailing down their chin.

Gaster had a sinking feeling.

~o0o~

Sans trudged wearily through the Waterfall caverns, heading for the Pure base near Hotland.

This was... bad.

It wasn't that he didn't want to destroy the Pure base; he did want to do that, quite a bit, actually. It was just that Papyrus and Gaster were in the Corrupt base, and Lord Chara was personally guarding them, and using them as leverage to get Sans to do whatever they wanted.

He couldn't let his family be hurt.

So that meant he needed to do everything Chara wanted.

Gaster and Papyrus would be stuck in the cell, but that was better than being stuck in a cell and tortured until they inevitably died, right?

... Right?

...

No.

No, he couldn't let them stay there. H had to get them out, somehow.

Somehow.

...

...

He was going to need some help.

~o0o~

Undyne was happy.

Okay, maybe happy wasn't the right word.

It would've been hard to he happy when Sans had tried to eat her Soul, escaped with Papyrus, Gaster had left, and everything had gone to hell the way it had.

But, whatever Dr. Gaster had done had worked, and after several extensive doctor checks, she was already back out on the field. Granted, she wasn't quite back to full strength yet, but she was most definitely close.

For the time being, Commander Gerson was still in Waterfall, helping her to run things.

It was a good thing he was there, too. Thrice already, the Corrupt had assaulted the base. Every time, the Pure had managed to hold them back, but Undyne hadn't been there for two of the attacks, and  the third she had only been working at half her usual efficiency. Had Gerson not been there, they would have been overtaken every time.

Undyne was making her way with Gerson to the mess hall. Much as they would both like to keep working, they did both need to eat.

Their progress was stopped by a shout. "Commander-s!"  They turned to look at the messenger. "Sir, Ma'am, I was told to tell you that you were needed in the debriefing room immediately!"

"Why?" Undyne questioned. She was hungry.

The messenger gave a half-shrug. "I was only told to tell you that. Rumor is, though, a Corrupter surrendered, and asked to talk to the acting Commander."

Gerson nodded. "Dismissed."

Together, Undyne and Gerson turned to the building opposite the base.

When they walked into the room, Undyne froze. Sans was sitting there, eyes closed, a guard to either side of the chair he sat in.

Hardly knowing what she was doing, Undyne lunged forward, summoning a spear to her hand as she leaped over the table.

She halted, crouched on the table, spear tip resting on Sans' chest. "Give me one good reason," she growled, "why I shouldn't just run you through, right here, right now."

When she had lunged forward, Sans had opened only his left eye. Now he peered up at her with the cracked orb of light, his right eye tightly closed. Undyne noticed there was sweat dripping down his skull. "c-could you-" he panted, "p-lease put th-that away? it-s a-already ha-rd enough to c-concen-trate-  without y-your m-ma-gic in- my face-"

"Concentrate on what?"

"n-ot e-eating--"

He really did look like he was having a hard time.

Slowly, Undyne withdrew, but didn't let go of her spear. "... Why are you here, Sans?"

He was quiet a moment. "... t-they have pap- an' gaster-... gonna hurt 'em..."

"Well, you only have yourself to blame for that."

Sans flinched. "don't... if- if i destroy t-the base, my lord said they w-wouldn't hurt them. s-so-..."

"So why did you surrender?"

When he looked up at her with his one broken eye, she could see his desperation. "b-because they- they'll just do it again." His voice was hoarse. "they'll just make me do more, and s-sometime i might not be able to do something-- and then-- pap-" he took a breath. "u-undyne- i can't not destroy the base-- but please- i- i wanna get my family outta there. l-listen. they d-didn't specifically tell me to k-kill everyone. e-evacuate- take all the weapons, all the supplies- let me destroy the b-buildings- then c-come help me s-save t-them."

"How do I know you're telling the truth?"

Sans spread out his hands. "l-look at- me, c-comm-ander! i c-can't- even open- my right eye- because it's too strong! t-the only thing keeping me f-from killing you now is- that papyrus- is in danger, and it doesn't matter- if i'm the one attacking him-... t-there is n-nothing i- can do without your help. please, commander! i d-don't want my f-family to s-suffer!" He was trembling by the end of his small speech.

Undyne glanced to Gerson.

He sighed, slowly. He had known Sans longer than Undyne.

"Sans. At the very least, we need a better plan."

Sans nodded.

Gerson sighed again. Then he gestured to one of the two guards. "You. Go. Call a mass evacuation. Tell everyone ta fall back to the Hotland base."

They guard nodded and ran out. Gerson and Undyne looked to Sans. "Now then. About that plan..."

§

A/N

Thanks for reading, and I hope you enjoyed it! Remember, votes and comments are not only always welcome, but always appreciated, too!