"A very long time ago Chara fell into Mt. Ebot,"
"That mountain over there?" Rosalina asked pointing.
"Yep," I said, "that one."
Chara cried for help. The prince of the underground, Asriel, found them and took them home. Chara and Asriel became good friends. One day Chara had an idea to free the monsters. They fell ill and later died. Asriel absorbed their SOUL and crossed the barrier holding everyone underground. Taking their body Asriel traveled to a village. Assuming he had killed Chara, the humans attacked Asriel. He didn't fight back and walked home very injured. Once he got to the castle Asriel collapsed and turned to dust.
"What happened to Chara's soul?" Rosalina asked.
"Well..."
Chara woke up following me around the Underground. I thought I was using self defense but I was murdering all the monsters. When everyone was dead, Chara had turned into a demon because of all the LOVE I gained.
"LOVE?"
"Level of Violence."
I fought my friend sans the skeleton. He kept dogging our attacks. I couldn't land a hit on him. Finally after killing me so many times, sans grew tired. Chara forced me to land a hit on him but I reset before they could kill sans.
"Reset?"
"Yea through the power of my DETERMINATION I reset the world to how it was before I killed everyone."
This time I spared everyone and we made it to the surface. Chara disappeared from my body and I never heard from them again. I found this big tree and made a gravestone for them.
"Oh," Rosalina said after my story. "That was very sad."
"Yea, I still have nightmares about killing everyone." I answered. " I need to go visit someone else. Would you like to come along?"
"Well, I suppose so. Where are we going?"
"Back to the Underground!"