Disclaimer: I do not own Undertale, or any of its characters.
Charlie had been staying with Toriel for two days. She felt welcomed here, and at home. She felt reluctant to leave, but she knew that if her friend could be alive then she would have to go and find her again. Charlie liked Toriel a lot. She was very kind, and gave Charlie books to read. She told Charlie stories about the history of monsters. She was also an excellent cook. Anything that she prepared tasted like it had been cooked by a God. Charlie noticed that Toriel was very happy to have Charlie staying with her, but at the same time seemed to know that Charlie's stay with her would be limited. The two were eating lunch when Charlie made the decision to ask about the human who had stayed before her.
"Toriel?" She said after swallowing a mouthful of delicious food.
"Yes, my dear?" Toriel replied.
"Can you tell me about the seventh human that stayed with you?" Charlie asked.
Toriel looked vaguely upset. She sighed. "Alright, Charlie." She said. "They were a young human, about the same age as you, sixteen or seventeen. They were a human of very few words. They didn't talk much, they communicated mostly through sign language. They had this look on their face. They were full of determination. They really wanted to return to the surface, they seemed to have someone up there who they cared for very much."
Charlie's eyes widened. That sounded like her best friend, her Frisk.
"What was their name?" Charlie asked eagerly.
"Frisk." Toriel answered. "Their name was Frisk."
Charlie's eyes welled up with tears. Frisk was alive. They were in the Underground. Charlie could find them, and finally have her best friend again. She could be properly happy again. Toriel noticed the tears in Charlie's eyes.
"My child, are you alright?" She asked, concerned.
Charlie nodded and wiped her eyes with the back of her hand.
"Frisk is my best friend." She said, and the tears welled up again and began to spill down her cheeks."My only friend. They went up Mount Ebbot and never came back. I thought they were dead, and I was devastated. I fell into depression, and I climbed the same mountain that they vanished on, with the intention of killing myself. I couldn't live without them. But when I jumped into the hole at the summit, I ended up down on the golden flowers, where you found me."
"I see," Toriel said. She smiled sadly. "I suppose this means you want to leave, to go and look for them?"
"I'm so sorry Toriel," Charlie wiped her eyes again. "But Frisk is alive. I have to go and be with my best friend again."
"I understand completely, my child." Toriel said, smiling softly. "Come, I will show you the way out of the Ruins."
She got up from the table and took Charlie by the hand. She lead her down the stairs, through a long hallway, until they arrived at a large door. Toriel turned to look at Charlie.
"Now, Charlie," She said, looking her in the eyes. "You must listen very carefully to what I have to say here, and keep it in mind as you journey through the Underground."
Charlie nodded.
"Not everyone in the Underground is friendly." Toriel said firmly. "Some are very opposed to humans. You must be very careful, and do not get hurt. However, if, by chance, a monster attacks you, you must not hurt them. There will always be a way to convince them not to hurt you. Have mercy on all of those you meet. Stay kind. I will miss you terribly, my child."
She wrapped Charlie in a warm hug.
"I'll miss you too, Toriel" Charlie said softly into Toriel's fur.
"Oh, and one more thing my dear," Toriel said.
"What is it?" Charlie asked.
"I must give you this phone," She produced a phone from her robes. "But I must ask you not to try to contact me, it would be too painful."
Charlie began to cry even harder. She had only known Toriel for two days, but Toriel already seemed like a mother to her. She was going to miss her painfully.
"I won't," She said tearfully. "I promise. I'll miss you, a lot."
"I will too, Charlie," Toriel replied sadly. "I will too.
So Toriel opened the door, let Charlie pass through, and then shut it behind her. And then Charlie was alone, in a snowy forest. She was cold, and she already missed Toriel sorely, but she was filled with hope and determination. She would find Frisk, and the two of them would return to the surface and live happily once again.