Adventure Time is not mine but it is totally mathematical. I make no profit from this story.

Big Sister

Chapter 1: Fever Dream

Fiona tossed and turned in her sleep. Her brow furrowed as she seemed to be fighting something in her dreams…

…She was sitting in a…in a car? She looked around it was dark and rain pelted the window next to her. She was very frightened. Next to her was a happy baby in a cute little hat with bear ears, he held a rattle in his left hand. In front of her a woman with curly golden hair sat. She shivered. There was a man driving. He looked nervous. A gurgling noise caught her attention,. She turned to see a baby strapped into what looked like a crib. She felt the need to reach for him her arms obeyed this need before she willed them to. It was hard to reach when she was buckled down but her hands grasped at the rattle. For some reason she grabbed it away from the baby. His little face scrunched up and turned red until he let out a loud wail.

The woman turned around and cooed at the baby and then the man looked back. He scolded Fiona.

"Give that rattle back to your brother," He shouted. Suddenly a flash of bright light blinded her. She heard screeching sound. She was flying… No, she was falling!

The girl sat up suddenly with a gasp. She held her hand up to her face it was shaking. Someone was sniffing like they had a cold. Oh…it was her. Something warm and wet slipped down her cheek.

"You alright over there Fiona sweetie?" A familiar and comforting voice called.

The young woman sucked in a shaky breath, "Yeah Cake…I…I'm fine." She kicked off her warm furs…too warm now that she had woken up. Before she could do much else a hand stretched across the room and lit the lantern. A little calico cat paw touched her forehead.

"You're warm baby," She tisked at her human companion, "Don't you move now. Cake will get you some cold water and a washcloth."

The cat disappeared down the ladder in the middle of their bedroom and could be heard rummaging around in the kitchen. She came back with a glass of ice water and a damp cloth. The cloth was pressed to her forehead. Fiona put her hand on it so the cat could have her paw back. The glass of water was thrust upon her and she felt compelled to drink it all. She swallowed too hard hurting her throat but didn't stop.

"Was it that dream again?" Cake asked in a cautious voice.

Fiona nodded and used the rag to wipe at her misty eyes. She wasn't a baby and crying wouldn't get her anywhere.

"We've searched all over AAA and there was no sign of Finn. I'm sorry sweet baby but you have to let go of this dream…He isn't-" Cake tried to comfort the girl.

Fiona's fists clenched, "Finn is real Cake…And somehow I'll find him! I will find you, baby brother."

"Alright Fiona baby, but not tonight," Cake patted her cheek and turned back to her own bed she looked bedraggled and tired. Fiona could not let go of this…Dad had found just her. There was no little boy with her…there was no sign that this-this "Finn" ever existed, but Fiona always had the same dream; a cruel dream tormenting her with possibilities and fears…

…Finn sat up and peeked through the darkness. He had that dream again. His heart raced. …Bright lights; a screeching beast; and screaming; and then nothing… He patted his chest to will his heart to stop racing. Jake snored quietly in his little cubby. Finn got up intending to get a drink of water. He lit the lantern. Jake squeezed his eyes and mumbled. Finn dimmed the light and went to the bathroom. He relieved himself and then went to the sink to wash his hands. He when he turned to go, in the dim light, just for a split second he saw a grinning figure. He turned to get a better look thinking someone was playing a trick, "Very funny Marceline, now were even but can you leave. It's really late." There was nothing in the mirror and when he turned nothing behind him.

He hummed and shrugged his shoulders, "Must be my imagination."

Finn went back to bed but had a disturbed feeling in the back of his mind the rest of the night…

…Fiona drew her sword and ran at the ice queen, "Give it up you dumb butt!" She kept her body between the evil cougar and the fair prince.

"Never! Prince Gumball is MINE!" The Ice Queen shrieked. She flew at the young heroine; her right arm stretched out and sparks of magic crackling from her fingers. "Ice bolt!" She screamed and began sending frozen projectiles at the girl.

"Fiona! Look out!" Gumball shouted his voice laced with worry.

Fiona deftly avoided the Icy shards that flew at her and jumped high in the air. The blue skinned woman made an ice shield and blocked, but as the ice cracked a fist flew under the breaking ice into the frozen villainess's gut. She grunted and fell backward.

"No fair, no fair, no fair, no fair!" She threw a tantrum then picked herself up. "You haven't heard the last of me Fiona! I'll be back for that hunky Gumball! When you least expect it! LEAST!" She flew off to sulk with her arctic pets.

The girl rolled her eyes and turned to the pink skinned young man, "You ok?"

"Yes," The boy smiled, "Thanks to you."

She blushed and looked at her feet. Kicking a rock candy pebble she shook her head, "It's nothing. I'm just relieved you didn't get molested by the Ice Queen."

Gumball shuddered briefly then nodded. He turned toward his palace, "Come we can have hot coco to warm you up. You're ice cold." They both laughed.

"Fiiiioooonnnnnaaaa!" The cute calico cat dashed down the street, "Are you alright? I'm sorry I was with Lord Monochromicorn." The cat jumped into her arms and Fiona continued walking next to the prince without missing a beat.

"It's ok Cake. It was just the Ice Queen. She's gone now. Lets go have coco With PG."

She smiled and looked to the prince. The boy hid his disappointment. He was truly hoping to have Fiona to himself for a while. Fiona is just so perfect. She's kind; brave; beautiful; funny; and very, very math. …But something always comes up; Cake interrupts; or the Ice Queen (or some other villian) attacks him; Marshall Lee whisks the pretty heroine away; or some other prince needs assistance. It's as if the universe is conspiring against him!

A figure watched from the darkest shadows. Gnarled hands caressed a ball of crystal that showed him images of far off lands.

"She's perfect!" A croaking voice announced to nobody, "And I know exactly how to obtain her. There is a way. Reunite the heros only to enslave them."

The shaded figure waved his hand and a new scene apeared. He grinned as he watched a boy. He held a sword in each hand as he fought a huge monster that was aparently made of mud. Yes these two souls would belong to him, and serve and protect him for the rest of their days. The creature cackled loudly. It rang through the walls of his home and frightened the wild life in the dark thick forrest surrounding his Shadow palace.