Explanation: This is an AU where Toriel remained queen (so kind of Swaptale) and Frisk traveled to the Underground as a pacifist, she saved Asriel from himself (Flowey) and used her own soul and Chara's to make his own. Unfortunately, his memories were were warped to prominently include both humans so his childhood with his sibling had no inclusion of his dad but does include Frisk.

The monsters then reached the surface and Queen Toriel decided to conquer the Surface with the help of Frisk as their traitor champion to boost moral, what they didn't know was that Frisk had been born with problems that only further crippled her during her journey. In the end, Frisk began to think of herself as a pet since she basically bent to Asriel's will, wore a nametag so he'd remember who she was since she looked so much like Chara, and was treated as less by monsterkind after humans were nearly made extinct; the few left sold as pets or slaves.

Because of this, Frisk was afraid she'd been sent back if she didn't act accordingly and tried not to let her weaknesses slow her down but, as time progressed, it only grew worse.

Dreadful Sorry, Clementine

He smiled, a furry hand touching a tanned nose that made it scrunch up as he giggled at the tiny thing. The human was not too much younger, in reality, but the lack of feeding had led her to grown small and lame in the legs so she hopped and crawled over walking. She blinked hopeful doe-eyes and he scooped her up despite the short whine that caught in her throat like most words; in truth, he'd grown to know it was a noise of approval despite the kick of little legs. The fur was warm but she squirmed regardless in mock protest in direct contrast to the joy she really felt at the attention.

"C'mon, Ch- Frisk! It's time to play!" He smiled warmly and she did in turn, it matched the look of approval as his mother briefly shadowed the pair before breaking off to her own path, it was the only time she didn't look tired anymore; it almost matched the look she felt slip for just a moment onto her face when she heard him slip...

Asriel easily navigated the building, the sun warming the carpets as the afternoon light seemed to flood through every window in the hall. Frisk's room was close by but mostly used for playtime since he liked having her close, this was outdoor time, though, she could sense it.

In a mere moment, closet doors were wrenched open to reveal pretty pink and cool blues that matched their frozen child-like image as he pulled the gloves over little hands and helped her into a pair of scarcely-used boots, furry but pristine despite this. Her lilac dress was left on but quickly covered by a tan coat, little lamb's ears sewn into the hood that nearly always covered brown hair during times outdoors; doll clothes, mostly, Toriel didn't like her wearing 'monster clothes,' she thinks.

He grabbed her hand and she stumbled down the hall, unable to voice the discomfort as it was lost in his excitement, "Asriel?"

"Yeah, mom?" He turned around, practically tripping the human was she ran into him.

"..." She seemed to hesitate for a moment, "Be back in time for dinner, okay?"

"Yeah! Yeah! I know!" He called back over his shoulder, still dragging along the girl behind him even as she grimaced, skirt fluttering up a bit to reveal the deep purple and withered black of her legs to match tiny feet and hands that no longer need their tight wrappings that marked her as a cripple so visually before. She'd been stupid to think his mother would have scolded him for something as tiny as her, as forgetting himself in excitement about the outside that humans had robbed them of for so long.

The frown was wiped off her face with a vicious motion as she dumped those emotions from her mind and focused, instead, on the warmth of the hand embracing hers and the blood still flowing, legs still moving, one of the last left to live. She didn't know if they'd keep her long but she'd long since stopped growing and was plenty cute; her life had even been lengthened thanks to their magic… The thought was scary, a dark nightmare that this special life of hers would be yanked out from beneath her feet as she was sold back into a different sort of slavery that could be much worse. But if she mentioned this concerns, let forth held back tears and emotion in the same old plee it would undoubtedly only contribute to the nightmare; better to just say silent. Never mention the horrid thumping on her throat from the collar and awful ache in her legs as she hopped to see his smile; because she really did love him, both of them, this was the one undeniable truth, an unchanging point. Better to stay ignorant too.

He tugged a bit harder and quickened pace towards the back door as Frisk carefully avoided her stumble and pulled the hood over herself; other monsters tended not to enjoy the sight of humans.

"Wow! It's so pretty out!" His beam matched hers like a reflection of the sunny disposition that was only appropriate on such a beautiful afternoon. The pond glimmered and they watched fish, he skipped a stone but hers fell from her hands and made nothing more than splashes and ripples in the pool. The rocks above the surface made for a fun game on less slippery days and the woods were still full of frogs and the birds that were so attracted to Frisk. They'd land on her shoulders and let each child pet their feathers through each caw and song as they preened and stole strands of brown hair from their clothes or white fur left behind on the ground. Hours of time passed with little notice as always, to dinner he went as she returned to her room but-

Heat flooded from the room and warmed her skin like she'd always preferred during those terribly short summer months and her cushion of a bed still covered in its overhang resonated just like it. It was a welcome surprise, playtime was the only passing meant for luxuries so she might cheer up the prince but this was something that shouldn't have applied. Yet, there she sat, instead of with her son, the queen sat upon her pet's bed and beckoned her to lay besides her.

A hand covered in fur that was so much bigger than the child prince's as she laid it upon her brown hair and shrugged off her dress. A nightly ritual she remembered so fondly even after it had been taken away as a nightdress of a length that just barely didn't drag on the plush carpeting of the room. Frisk felt swathed in a love she hadn't felt in a long time, a mother's comfort rather than an owner's or sibling's that was almost akin to… The skin-on-skin contact of a hand that matched her own and a similar smile of dulled teeth, she'd put her hair in- The same stilling in the strands as they slowly are weaved together into a knot; the human disappeared, better this than a memory.

"I have festered this hate, maybe in hopes to keep you as you are, less…" She seemed sorrowful, "But...it is because of you that we rule, that my son still lives, it's a shame he can only remember Chara…"

Frisk let her eyes drift upwards and her throat squeezed but she still- she had to… "Mmeh-" It began, catching in her breath as she swallowed the thickness beneath the collar but felt another soft touch, careful as it unhooked the metal and slid off the offending object.

"Shh...it's alright, I know it hurts…"

"Nn..non, h-happ...happri." She coughs a little, ignoring the shock on the queen's face, "Eh- I…" If she could just...voice it, just this one time, her desire, if she could be allowed to simply say it without worry- "Hurr tuh. Bah...arr fahmiri...mmmeh- mom." Tears seem to come to the woman's eyes as one hand leaves the girl to cup her mouth in shock.

Frisk's eyes fight darkness, so warm...so much comfort it could, maybe, keep out the nightmares but she wants to be awake for this, "You called me…" The self-hatred is clearly shown in her eyes, "Why…? After all I've done since you saved monsterkind...I hurt your people."

It's a sad smile she's returned with, "Riiii-keh, them. Fell forh essss-cape. No haahte, bah no ruv; non ri-keh you."

"My child...I'm so sorry!" It's all here, like a dream come alive, a world where it was real concern as she watched the human child stumble and fall as she was pulled haphazardly, where doll clothes simply mark her as untouchable to would-be hunters, and, perhaps, she could be a child once more…

Tears began to sting her own eyes, little hands tightening on Toriel's clothes as she held her, "Purrease...don' giiiv bac."

"What?"

"'M non soup-osed to...to…"

"No, child, it's alright… This is my fault, you are so small...so fragile, now. You fought our wars but...it hurt you like all of us, I just did not want to see it," Her eyes shown through with deep sympathy and a hint of consideration, "Frisk-" The girl's head shot up to stare at her in shock, "-You are just a little girl... Know that tears are natural, as is frustration and the need to scream when in pain. Please, don't be afraid to show those things to me anymore. Without a voice, I need to be corrected of my mistakes in some manner."

It was a watery smile but the truest she'd shown in a while, a brief nod full of hope and determination was quickly shared as it seemed her world would finally change; a change for the better, this time.

And the next time Toriel saw Asriel's tugging she'd yell, "Asriel! Don't pull Frisk around like that! You need to be patient if you want her company, she doesn't have to give it to you!"

And the next time dinner came around a chair was set out with another cushion atop it to account for height. The next night in her room spent in the blissful warmth of heat and magic as the next morning came she was asked, "Do you want to change your room, Frisk?"

A few afternoons were spent in pleasant silence, stars glowing on the ceiling as the lights were turned down or sun easily coming in through a window she could finally reach; a blanket much thicker lay by her bedding but little else differed. The wardrobe was still full of dress-up clothes and little additions like softer shorts and striped shirts like Asriel's.

A few nights were spent tuckered-out and dreamless but others felt a mother's comfort as she willed away her dreams.

A few mornings were spent on her own, Asriel being lovingly refused or angry shut out as she remained much more passive than most but firmly exercising her freedom. The little tag Asriel had grown up reading was displayed on her door and pointed to at any mistake with a harsh meaning but not too harsh a lesson as she knew he only missed his sibling.

Little whines still meant 'okay' but other sounds were headed better as he slowly curved into learning better, teachings having changed since days spent with Chara in a glorified practice of torment towards their pet. He'd never had her streak of sadism, thankfully, but such a loss had painted both childhoods in an obvious screen of misery left behind by the soul he'd been given. In the end, life was changing and so were people, it was a good turn to a bitter tale (though Frisk had never been) and a fitting ending to The Tale of the Monster War and its main victor, the human traitor.