I got this prompt from Devi-Yosh in their "Undertale Tickle Drabbles".

Undertale belongs to Toby Fox. I own nothing.

Prompt 31: Please Don't Leave Me

Frisk was trying to get away from the lockers before the bullies spotted her, but they were quick to spot her as they were waiting by her locker, even though she had grabbed all her stuff earlier so she wouldn't have to go to her locker at the end of the day.

"Finally showed up, huh?" The lead bully sneered.

"Where you going, freak?" Asked another bully.

"My dunkle is coming to pick me up," Frisk said and went to move away, but one of them caught her backpack and pulled her back.

"How long do you think that will last?" The first bully asked her. "Do you think he'll really care about you later on? They never do."

"Yeah, just like your real parents did, that so-called 'dunkle' of yours will abandon you too," said a third bully.

Frisk didn't want to hear anymore and tugged her backpack away from the bully that had grabbed it. "No, he won't," she said. "He's way better than my birth parents were. He'd never do that."

"They always do," said the second bully. "Who would want another person's kid and all that kid's problems?"

"Yeah," said the lead bully. "It's the same thing all the time."

Frisk now just ran, bursting outside and quickly looking around, spotting Sans instantly and running up to him.

The blue hoodie-wearing skeleton saw her running up to him and instantly noticed the tears in her eyes. He immediately knew something was wrong and her clinging tight to him when she reached him proved something was very wrong.

"Frisk? What happened? Bullies?" He asked.

She nodded, but didn't stop clinging to him. Normally, if it was just bullies, she'd loosen her grip on him so he could pick her up and go take care of the bullies. He noticed that her grip got tighter and he knew from experience that she'd only do that if she felt insecure.

Which meant someone had said something to her that possibly triggered a flashback of her life before meeting the monsters.

It took everything in Sans to not go storming into the school to go find the bullies that hurt Frisk with their words, but then he saw Frisk's teacher come out and she looked relieved when she saw the child was safe in his arms. Sans looked up at her.

"What did those bullies say to my kid?" He asked the teacher, trying to keep his voice level despite looking ready to explode in anger.

The teacher looked saddened. "They told her that she'd be abandoned again, just like she was by her birth parents," she said softly.

Sans stiffened up. "Please tell me you spoke with them," he said.

She smiled a little. "Even better. They will be attending class in the room by the principal's office," she said.

The room by the principal's office was one where students who were disruptive or bullied others went and had to do extra schoolwork under the principal's watch and the principal himself was strict and didn't allow any nonsense while he was teaching. And those students were only allowed to return to their normal classroom if the principal felt they had learned their lesson.

Relief filled Sans at that because that meant Frisk wouldn't have to deal with the bullies again. "Thank you," he said to the teacher as he then looked down at Frisk and gently squeezed her shoulder. "You have homework, kiddo?" He asked.

Frisk was about to answer when the teacher spoke up. "Actually, Frisk, may I see the homework paper I gave you?" She asked.

Curious, the child gave the homework paper to her teacher, who smiled. "When you left, I happened to see that you had already done some extra credit that I had passed out a couple weeks ago," she said. "I was about to tell you that I had mistakenly given you homework when I overheard what happened at the lockers.

"So, in lieu of you doing the extra credit work and getting an A on all of it, and given what you just went through in the hallway, you don't have any homework and, I forgot to mention this but the principal just announced it right now, there is a teacher's meeting tomorrow and the day after, so you and the other kids have a four-day weekend."

Frisk looked surprised at not having any homework. "I got a good grade on the extra credit assignments?" She asked.

The teacher nodded. "A's on all three of them," she said. "So that will count toward your final grade at the end of the year."

The young girl smiled just a little. "Thank you, ma'am," she said.

Sans smiled. "I think you just made it to the top of my list of teachers I like," he said to her.

The teacher smiled at that. "Just doing my job," she said modestly. "Take care. See you Monday."

Frisk bid her teacher goodbye and looked up at Sans, who nodded. "Shortcut?" He asked knowingly.

She nodded and Sans picked her up in his arms. She immediately held onto him as he teleported home. Frisk went upstairs and placed her backpack in her room before going over to lay down on her bed, but a blue aura surrounded her. "Hold on there, kiddo," she heard Sans say. "We need to have a chat."

She then felt him gently turn her upside down with his telekinesis and she giggled a little, which made him chuckle and carefully turn her right side up and set her down, but as soon as he let her go, she raced out of the room. Cocking an amused eyeridge as he knew where she was going, he followed and saw her run into his room. He entered just in time to see her hide under the blanket on his bed.

Chuckling, he shook his head before grinning and going around to the other side, seeing the kid curl up under the blanket to stay still, but he lifted up one side of the blanket carefully and saw the kid's back facing him and so snuck his hand to the young girl's side to give her a playful poke in that side.

Frisk let out a cute squeak and jumped as Sans removed the blanket to reveal her hiding place and caught her. "Gotcha," he said with a wide grin as she giggled louder before her giggles died off and she looked upset. "Frisk, what did those bullies say to you?"

She flinched. "Nothing," she answered.

Sans shook his head. "Nope, I want to know," he said seriously, seeing the kid look away from him as tears began falling down her face. A gentle, skeletal hand cupped her cheek and gently turned her head so that she was facing Sans again. "Come on, kiddo," he said, his voice taking a soft, encouraging tone. "Tell your good ol' dunkle Sans what happened. You know I'll listen."

Frisk looked up at him, her small eyes shining with tears. She suddenly clung to him and he wrapped his arms instantly around her in a hug as he heard her start sobbing into his hoodie. "S-Sans?" He heard her ask after a moment.

"Yes, kiddo?"

"Please don't leave me."

Sans' eyes widened in shock and he took a deep breath to gather his thoughts. "Is that what those bullies led you to believe?" He asked. "That I'd leave you someday?"

Frisk nodded. "They said…you'd abandon me…just like…,"

Gentle fingers brushed soothingly over her face and she looked up to see Sans giving her a very serious look. "Frisk, I swear to you, kiddo. I'll never leave you," he promised.

She looked up at him. "I thought…you didn't like to make promises," she said softly.

He smiled. "I made an exception for Toriel when she asked me to keep you safe when you first came to the Underground," he said gently. "I can make an exception for you too. Any promise I make to you, I won't ever break."

She sniffled and felt him wipe away her tears. "You promise you won't leave me, ever?" She asked.

"I promise," he said sincerely. "You're my baby bones, kiddo. You have been ever since you began living with Paps and I in the Underground."

Frisk smiled a little. "Really?" She asked. She had noticed how when she lived with the brothers, Sans seemed to become more protective of her and now it made sense. He had basically adopted her right then and there.

"Really," he said with a nod, smiling as Frisk snuggled into his hug.

"You're a better daddy than my other dad was," she said honestly.

Sans smiled and rubbed her back before grinning. "Thanks, baby bones," he said. "Now are you going to give me a real smile or is Daddy going to have to tickle it out of you?"

Frisk giggled at that and looked up at him. "Tickle?" She asked hopefully.

Sans grinned. "You want tickles from your awesome dunkle?" He asked with a knowing smile, making the young girl giggle as she nodded and he set her down on the bed and grinned, raising his hands and she giggled as she saw his fingers wiggle at her teasingly. "Okay, then. Since my baby bones wants tickles from me, that's what I'm going to give her."

Gentle, bony fingers began tickling her sides and Frisk began giggling. "Man, I can't get over how cute your giggles and laughter sound," Sans said honestly as his tickling fingers now tickled the young girl's stomach, making her burst into laughter. "Your laughter and giggles are some of my favorite sounds, kiddo, did you know that?"

Sans gave her a breather and Frisk took a couple deep breaths before looking up at him. "They are?" She asked in surprise.

Sans chuckled. "Your giggles and laughter brought hope that we monsters would be freed soon when you were in the Underground, kiddo," he said, helping her sit up, giving her ribs and underarms a gentle tickle in the process, making her giggle again. "Best of all, it was easy to make you laugh then and still is."

Smiling, Frisk lifted up her arms out to him and he picked her up, hugging her and gently rocking her. Sans then gently nudged her shoulder, making her lift her head to look up at him. "So, do you believe me when I say I won't leave you, kiddo?" He asked, sneaking one hand up to Frisk's neck and wiggling his fingers playfully into her neck and over her ears, making her giggle again before she caught his hand and he chuckled.

Frisk then looked at him. "I believe you, Dunkle Sans," she said and hugged him again, snuggling her face into the fur of his hoodie.

"Good," he said softly, sitting on his bed and rocking the young girl in his arms gently and feeling her start to go limp in his arms. "How about we rest our bones?" He asked her, smiling when she giggled softly. "I can tell you're bone-tired."

Frisk giggled again and nodded, but didn't move from her spot in his arms. "Sleepover?" She asked, giving him puppy eyes.

Sans chuckled. "Sure, baby bones," he said as he lay down on his bed and zipped her up in his hoodie. Frisk lay her head down on his chest, hearing his heartbeat. She then saw Sans' right hand glow blue and watched the blanket glow blue before it gently covered her and Sans.

"There we go," the hoodie-wearing skeleton said. "All warm and toasty."

Frisk let out a happy sigh. "Love you, Daddy," she said softly.

Sans smiled. "I love you too, baby bones," he said.

"Stuck with you forever?" She asked.

"Stuck with you forever," he said with a nod, watching her fall asleep. He watched her sleep for a bit before feeling his own eyes struggling to stay open. "Nothing in the world could ever make me leave you, kid. Nothing at all."

With that, Sans closed his eyes. "I'll never leave you," he whispered softly as he fell asleep, holding onto his little baby bones protectively as night came.

I just can't help it. These family moments are the best. :)

Please leave a review, but no flames!

GoldGuardian2418