"I can't wait to get back to the surface, though I don't know what I'll do once I get there." Sam said, looking up from their sketchbook. 

"Wouldn't you want to go back to your family?" You asked them. They sighed, setting down their pencil. 

"They never cared much about me, and after all you guys are my family now!" Sam exclaimed as they went back to drawing an anime boy. So they were a weeb. That explained the endless quotes you never understood and their sketchbook full of anime. You thought of Sam as your little sibling, from the way you talked and acted people would think you were siblings.

A few hours later, around lunch time, you got word of a human coming through the door to the Underground. Frisk. Chara had no control of the world anymore, so there was no way to predict what would happen. 

Sam decided to stay home while you and Sans went to go check on the human and greet them. Frisk had dust on their hands and sweater. No. Not again. You ran away to warn Sam and Papyrus. Sam was surprised at first, but they left without a word. They ran until they were out of your sight. Why did Frisk do this again? One could never predict them though. Determination was something that couldn't be reasoned with. 

The three of you waited in the judgement hall, all knowing what came next. You knew you were going to die, but it was worth putting up a fight. Sans was first. He was lazy, so naturally Frisk went for him first. Now it was only the humans. You were so hurt by grief of losing Sans, though it was as if you had lost a lover. You were caught off guard by a knife's swing, falling to the ground holding your stomach. 

Your determination will not phase me, so come at me with all your will

My soul is stronger, burning brighter with the ones you've killed

I am known as patience, retribution, and I'll drag you to underhell 

'Cuz kids like you should not exist, I know you won't be missed.

Though there's no laughter here, silence exists all around

The empty world you've bought will damn you to the ground

I thought you once were good, but motives came to be clear

I gave you trust and love, and you created fear.

Yet, like flowers blooming anew, the world reset again. Maybe this time, the world would be free to live a pacifist route and go to the surface. Frisk was nice this time. They didn't kill anyone. Their behavior was indeed extremely unpredictable. Determination is a strange trait, certainly a strong force.