( Sorry for this being a short Chapter, but hey, the last one was really long.)

Sans led the way through the forest, Frisk struggling to keep up with him, surprised by how agile he actually was. If he hadn't had a death grip on their hand, they were sure they would've lost him by now. He seemed to know the woods like the back of his hand, not seeming to be bothered by any object that got in his way, already expecting it to be there.

He made a sharp turn, suddenly looking down at his chest, then behind him and past Frisk concerned.

They gave him a curious look, but he quickly turned back around, continuing to sprint between the dense woods.

" S-sans," Frisk began, breathing hard, "D-do you know wh-where you are g-goING--!!"

He suddenly jumped, ripping Frisk with him. Frisk saw them heading straight for a rock and yelped, expecting a hard impact and closed their eyes tight, only to not receive one.

They slowly opened their eyes to see they were in some sort of den or cave, the only light coming from Sans' illuminated eyes.

They watched the eye-lights move to the other side of the small cave, putting his hand on a some-sort-of box. Suddenly, the whole room illuminated with blue and yellow light.

Frisk looked up, to see a translucent shell above them. That must of been what they had thought was a rock.

Frisk looked towards him, not sure how well he could see them and began to ask, "Sans, where are-"

He put his finger to his teeth, hushing the child.

Frisk frowned, signing the question instead, "(Where are we?)"

Suddenly, strange symbols began appearing above Sans, while he just continued to look at Frisk, blank faced.

Frisk looked at the symbols bizarre, their face scrunching in confusion. Sans got the hint that they didn't understand what he was saying, and waved them off, putting one finger up, indicating to to give him a minute, as he headed over near the entrance of the den.

They watched as he pressed a code into some odd looking tiles on the wall. A white box slowly moved out of the wall. He took of the lid, and placed the palm of his hand into the box. When he retracted, Frisk could see a red shimmer on his hand.

Determination

He placed his hand into the center of the translucent barrier. It seemed to suck the determination clean off his hand, before suddenly becoming solid. He knocked on it in different areas a few times, seeming to be checking it's stability before turning to Frisk, who was gawking at him.

He raised a brow at them, "what?"

Frisk continued staring dumbfounded.

"kid...you can talk now...or move...or do anything but make that face," he said staring back at them.

Frisk blinked at him, "(What on earth was that?!)"

Sans shrugged, "a mini barrier."

"(Why do you have...A MINI BARRIER!?)" Frisk signed, their arms being thrown up in the air to further their point of confusion.

"uh", he looked to the side, "my um, dad, made it as a hideout if a dangerous human came down here... it's actually a lot bigger, but there needs to be more monsters to access the next area... no one except me, papyrus, and the king know about it... he kept it a secret from the public to avoid kids getting themselves trapped down here, or lost."

Frisk felt something strange turn inside them, as he mentioned 'a dangerous human' but decided to ignore it.

He pointed to the roof, " once it seals no one can exit or enter, unless you are on the inside and know the code, which again, only three monsters in the underground know it and we are only allowed to share..." he paused, " under special circumstances."

Frisk, looked at the roof, "(So, Undyne can't get in?)"

"nope," Sans nodded.

"(And neither can Papryrus?)" Frisk asked.

"not from the side he's on," Sans winked.

Frisk looked hopeful, "(So we're safe?)"

"well," he rubbed the back of his skull, "we're safe until we leave... then we are probably gonna be in a heap of trouble if Undyne goes off telling the Guards 'bout it."

"Oh," Frisk sighed.

" hey, don't look so down, kid," he tossed a book at them from his hoodie, "here, this will keep you distracted for a little while."

They looked at the cover.

The Outsiders

Frisk scrunched their nose up at it, seeing it had chapters.

Sans rolled his eye-sockets, taking out a book for himself. Frisk could swear that that hoodie also had an elephant in it with how much stuff he managed to fit in it. "trust me kid, you'll like it."

                                                                 ******

" WHAT DO YOU MEAN THEY ARE RIGHT HERE?!" Undyne screamed at the skeleton.

" I-I, I CAN SENSE MY BROTHER, H-HE'S RIGHT HERE.... I-I JUST--"

" You just what!?" Undyne yelled grabbing him by his scarf.

"WELL, YOU SEE..." Papyrus put his fingers together, " HE'S A-ACTUALLY BELOW US..."

Undyne paused, letting it sink in, before her brows furrowed back up in frustration, "WHAT!?"

" BUT, Y-YOU CAN'T...YOU CAN'T..." He trailed off.

"Speak!" She commanded

" YOU CAN'T...GET TO... him..." He looked away, ready for her to scream again.

And scream she did. "NGAHHHHH!" she screeched, stamping her foot on the ground, "I'M TIRED OF RUNNING AROUND TRYING TO CATCH A STUPID HUMAN!" She stormed away, Papyrus watching her weave through the trees.

"W-WAIT!" He called after her, "W-WHAT ARE YOU GOING TO DO!?"

She froze, before turning around to him, her eyes cold, "They're going to have to eat, yes?"

Papyrus nodded, confused.

"I'm going send a red alert to the whole underground... if they see a human, they must kill it, no matter what, or there will be repercussions..." A spear flared up in her hand, "That goes for you too, Papyrus."

"BUT--"

"No, buts." She said, glaring at him, "You see them. You KILL them... understood?"

Papyrus bowed his head, "Y-YES, UNDYNE..."

She smirked, "Good." Then she calmly headed away.

Papyrus gulped, looking at the rock he knew his brother and the human were hiding within, "I'M SORRY..."

Papyrus ran away.