Sans appeared just outside his and Papyrus’ house, only to be met with his worst fears. Dogaressa had beaten him here…and she was talking to Papyrus.

A pit formed in Sans’ stomach as he froze in place momentarily…staring at the dog as she appeared to be speaking very fast, a stern look in her face. Papyrus faced away from him, his arms crossed as he nodded and listened to what Dogaressa was reporting. Sans could guess what she was saying…and it only made him that much more anxious.

Shortly after he appeared, Dogaressa noticed him. She abruptly stopped speaking and her eyes widened before slowly narrowing. Papyrus turned his head slightly to look behind him to see what Dogaressa was looking at, and as soon as he saw it was Sans, his expression changed to one of concern…disappointment…

Papyrus muttered something to Dogaressa before turning around fully to face his brother. Dogaressa then quickly saluted Papyrus and took off on all fours, leaving familiar footprints in the snow.

Sans watched her go with wide eyes, his hands shaking slightly, before looking back at his brother. Papyrus’ frowned, then slowly began to approach Sans.

Sans tried to smile at him - as is his usual instinct to mask his true feelings - but seemed to fail miserably this time.

“P-Pap…”

Was all Sans could really say. He didn't know what to say. How much Dogaressa had heard. How much Papyrus knows.

“Brother…”

Papyrus began, wrapping his arms around himself, seemingly trying to comfort himself after hearing such dreadful news.

“I…”

Papyrus sighed, his brow furrowing, seeming like he was having a difficult time finding the right words.

“I did not anticipate that …where you've been disappearing off to all these years…”

He paused, closing his eyes and taking a deep breath.

“This can…still be fixed.”

Suddenly the dots began connecting in Sans' head. The reason Papyrus was acting so weird this morning…Papyrus…he knew. He knew that Dogaressa and Dogamy would follow him.

“You…sent them to follow me?”

Sans was in utter disbelief. He felt almost betrayed.

Papyrus opened his eyes and looked back at Sans. His expression serious.

“Sans…you will be marked as a traitor to the kingdom and that’s what you're focused on?”

His frown deepened.

“It was a decision made by Undyne…but…I agreed to it. Told her that I was so sure that you were doing nothing wrong…”

Papyrus sighed incredulously.

“What you have done is very serious, Sans. But it can be fixed. Please…just…help us turn the human in. Tell them you were tricked. I'm sure the King will understand…”

Sans’ brow furrowed as he heard this solution.

“I wasn’t tricked! That human is my best friend, Pap. I…I promised I would keep her a secret…because I knew she would be killed otherwise. She's not what you all think! She's my friend.”

Sans desperately tried to explain himself, hoping Papyrus would try to understand…but he knew deep down that it was too late. Dogaressa had gotten to him first and likely told him a story that would be difficult to refute.

Papyrus' frown turned into something much more serious.

“It is a human, Sans! You know what humans do! How they are! It is manipulating you! Open your eyes, brother! Do not get yourself killed over a trick!”

Sans clenched his fists. His hope of getting Papyrus on his side was dwindling more and more.

“She. Is not. Like that!”

Sans was growing desperate. If he couldn't get Papyrus on his side…all hope was lost. He took a deep breath.

“Pap…please. Just…listen to me! I…I can show you. You can see for yourself.”

He pleaded with his brother, desperation in his eyes.

Papyrus grimaced, shaking his head. He took a step back, putting his hand on the hilt of his sword.

“I will not give the human a chance to try and trick me as well, brother. I cannot. We have a duty as Royal Guardsman. And if you are going back on your oath, then I will simply have to knock some sense into you before it's too late.”

He drew his sword, blunting the end as a means to only try and incapacitate Sans rather than kill him.

“Please…don't make me hurt you.”

His voice cracked, but his face remained serious. Clearly this whole ordeal was very hard on him…but he was determined to stop his brother before he made things any worse.

Sans looked at Papyrus’ sword, now being pointed directly at him. His mouth opened slightly in disbelief at what was happening. His own brother…wouldn't even believe him. Again. It was just like when he tried to tell him about their father. His heart sank.

“You…you never believe me.”

He closed his eyes, fists clenched and jaw tight. After a moment, he opened them back up, glaring at Papyrus. He put a hand on his chest. Frustrated, saddened…

“Why don't you ever believe me!?”

Papyrus’ grip on his sword faltered slightly, his brother's words hitting him hard. But he quickly tightened his hold firmly.

“I’m doing this because I love you, Sans! You know the penalty for treason! If you won't stop this on your own accord…this is the only way to save you!”

Papyrus’ hands shook a bit as he tried to find his resolve. Then suddenly, he lunged at Sans - trying to knock him out quickly.

Sans immediately summoned his bone staff, blocking Papyrus’ blow and faltering slightly under the sheer weight of his swing. He knew his brother was strong…but he had never gotten a proper glimpse of just how strong he was. The closest they've ever been to fighting were sparring sessions - and he knew all too well that they both held back. He could tell now, however…that Papyrus was no longer holding anything back.

Sans arms shook under the pressure of Papyrus’ sword.

“Pap…just listen to me! Please! Give me a chance to prove it to you!”

Sans pushed back, struggling to lift Papyrus off of him, but it was in vain. Papyrus was simply stronger than him. Sans quickly teleported away and behind Papyrus instead, watching his brother stumble forward. Papyrus quickly regained his fighting stance and swung around to face Sans again.

“There is nothing to prove! A human is still a human! You should know better, brother!”

Papyrus lunged again, his sword clashing with Sans’ staff.

But Sans was better prepared this time. He put all his weight into pushing Papyrus back - their swords fighting against each other's force.

“You just…don't…understand!”

Sans struggled against Papyrus, desperately trying to get him to listen as his pushed his staff against his brother’s sword. If he could just…drag this on long enough…tire Papyrus out…maybe he would eventually listen. It was the only hope he had left.

But suddenly…

CRACK

There was a sickening cracking sound. Sans’ eyes darted to the source - his own staff. He saw it…for just a brief moment he saw the crack that had formed due to the excessive force of their weapons clashing against one another. But before he could do anything -

SNAP!

His staff snapped at the end where their weapons were colliding. The blunt end breaking off and leaving him with a jagged and sharp point. Him and Papyrus both fell towards one another as his staff broke in two, Sans closed his eyes to try and brace for the impact of Papyrus' sword.

But the blow never came. He slowly opened his eyes again, and was met with absolute horror.

Papyrus was lying limp on Sans’ broken staff. Sans’ eyes widened and slowly drifted down towards his hands that were still gripping his weapon.

“...No.”

His breath shook. There was…blood. So much blood.

“P…Papyrus…?”

Sans quickly let go of his staff, grabbing Papyrus and carefully turning him over, falling to his knees. His staff was still stuck in him, having impaled his brother right through his neck. Papyrus seemed completely unconscious, and slowly…flakes of dust began to drift off of his face.

“PAPYRUS!?”

Sans shook his brother, trying to get him to wake up. His breathing slowly grew erratic, his hands shaking.

“WAKE UP!”

Slowly…Papyrus began to crumble. The dust drifting off his face growing thicker and thicker…until Sans was soon left holding nothing but an empty shell of Papyrus’ armor, filled to the brim in a heap of dust.

Sans stared, gripping Papyrus’ armor. His breath shook and he could feel his eyes begin to sting. He shook his head, denying what he just saw…what he was currently looking at. His brother…dead…and by his own hand…

He started to panic. He stood up suddenly, dust covering his own armor and clothing. He looked down at his bloodied and dusty hands.

“No…no no no no…”

His head shook as he took multiple steps back. This was a nightmare. It had to be a nightmare. Sans started smacking himself in the head, trying to get himself to wake up. It wasn't working.

“Wake up, wake up, wake up!”

He wasn't waking up. He started pacing a bit, glancing at Papyrus’ dusty armor over and over again. He had to accept it…accept what just happened. Slowly…he was, but his acceptance came with a new fear - not only had he killed his own brother…he had just killed a commander. He put his hands on his head, still pacing. Everything was getting worse and worse.

Then he saw them. Someone was standing nearby, mouth open in shock. Another Guardsman. Lower ranking…a semi new recruit. They had seen everything. Seen Sans kill Papyrus.

Sans stared at them, equally as shocked. A moment passed with them just staring at each other, until the Guardsman took a step back in fear - seemingly settled on what they needed to do now. They had to run…leave…tell Undyne what had just happened. And Sans picked up on that quickly. Before the Guardsman could move another inch, Sans acted fast, acted on pure fear of the consequences that would come with him being reported for this.

“-No!”

Sans exclaimed, raising his arm towards the Guardsman and summoning a dozen bones that shot up out of the ground at their feet, skewering them. The Guardsman went limp, falling forward a bit and being held up by nothing but the bones impaling them - before they, too, started to turn to dust.

Sans continued to stare…completely paralyzed by what he had just done. He acted out of fear…nothing more. And now another monster was dead at his hand. He slowly lowered his arm, staring at the now empty armor and dust that was slowly falling to the ground. His eyes drifted back towards Papyrus’ armor again, his expression quickly changing through the different stages of grief. Denial. Anger. Bargaining. Depression…Acceptance.

Acceptance of what he had to do now. Papyrus was gone. A commander dead. Another Guardsman dead. There was no hope of convincing anyone anymore. There was only one path left for Sans to take. Only one way he could save Frisk.

He had to kill them all.