It was a quiet, almost eerie morning aboard the ARK.

Between the sound of his air shoes walking along the metal, sterile halls, the sound of his breathing and the hollow echoes that followed him, Shadow felt the uneasiness in the air.

Normally by this point in the morning, Shadow expected to run into the two kids of the ARK wandering around throughout the facility. The sounds of annoyance, play and laughter coming from them as they alleviated their boredom aboard this lonely vessel.

Instead of this, there was mostly ambience. A near complete silence that only meant one thing to Shadow.

Maria must of woken up sick again.

The young girl had been diagnosed with a rare and incurable condition known as Neuro-Immune Deficiency Syndrome. On Earth, her condition couldn't be treated. However, her grandfather had taken her to live aboard the ARK while he attempted to find a cure for her sickness, much to her family's dismay. Since her arrival, he had been experimenting with different avenues of the medical field, trying anything he could to somehow make her feel better. Yet no matter how many tests they did, fusing Shadow's DNA with diseased cells to see their reactions, attempting to combine Shadow's healing properties in his cells with immunosuppressant drugs; their efforts had been in vain.

He sighed nervously, hoping he was wrong. Maybe she'd just slept in? Maybe her and Abe were reading or playing somewhere else on the labyrinth they all called home. But Shadow could feel tension as he moved towards the infirmary.

He had to find the Professor. Ask him.

Thankfully the Professor's lab was rather close to the infirmary wing. Picking up his pace, Shadow raced down the empty halls and corridors towards his creator's study.

He'd never admit it to Gerald, but Shadow was feeling the pressure of his purpose every time Maria got worse.

Opening the door to the lab hastily, Gerald jumped in surprise as the black hedgehog skidded into the room. Wearing his usual white lab coat, pristine and sterilized like everything else in the facility, it gave the man a look of confidence and intelligence. His proud moustache normally clean and groomed however looked messy. Gerald's eyes wore heavy bags from insomnia as he appeared to be holding in the need to yawn. Clear indicators of stress and worry.

Something's wrong.

"Morning Shadow! Scared the daylights out of me!" Gerald scoffed, raising a hand to his chest. He then sighed, trying his best to calm down. "Honestly I think you might of jolted me awake a little. It's been a long night."

"Good morning Professor. I'm sorry for startling you. Have you seen Maria?"

Gerald sighed uneasily, looking past Shadow and towards the door behind him.

"She's not feeling well today." He said sadly, a frown forming on his face. "Her condition is making her feel like she's unable to move around very much. Severe levels of exhaustion."

"Is she stable?" Shadow asked promptly. Thankfully for the hedgehog, he watched his creator's face relax slightly.

"Yes she is stable thank goodness. But she's going to be in the infirmary until her condition improves a bit more. I think today we can skip our usual testing so you can spend time with her. Maybe that will cheer her up?"

Shadow nodded in agreement, "I'll go see her."

Gerald looked at his creation and smiled, placing a hand on Shadow's head before gently ruffling his quills.

"That's my boy." He said proudly. "I'll be in there periodically to check on her vitals. Just make sure she's comfortable, okay?"

"Yes professor, of course."

Without any hesitation, Shadow skidded out of the room and back into the hallway, racing until he was face to face with the infirmary door. He took a deep breath, preparing himself.

This was going to be a tough day.

The doors opened automatically, hissing and clanking until they revealed the room behind them. The infirmary smelt of antiseptic, fresh linen and plastic; environment clean and sterile. He gazed at the first bed in the room, finding the girl resting with an IV in her arm to keep her medicated and hydrated.

"Maria." Shadow called to her as softly as he could, causing the girl to slowly open her eyes and glance over at him as he slowly walked up to her bed.

" …Shadow?" Maria answered in a rasp, her voice strained from fatigue and her condition. Dark circles formed under her eyes. She weakly smiled at him.

"Maria are you okay? How are you feeling?"

The girl groaned. "I'm really tired today. Every movement feels like I'm going to exert myself, so grandfather has told me not to leave the infirmary until I'm doing better…"

"It's okay, just take it easy." Shadow said affirmatively, trying his best to avoid thinking about the times she's collapsed in the past. Every time it has happened, Shadow's heart hit the floor as he would dart to her as quick as he could to catch her before she hit the metal floor below. No matter how many times it's happened, it would still scare him.

Maria looked at him with a sad but welcoming face. "I could really use a hug right now, but I don't think I can get up."

Shadow looked at her with a sad expression. He felt so powerless when she was like this. He immediately hugged the girl as best as he could without moving her too much, trying his best not to accidentally hurt her. After a long hug, Shadow tried to pull away. However Maria placed her hand onto his arm as he moved, causing him to stop and look up at her.

"Do you mind laying here with me? Until I feel better?" She asked nodded, jumping onto her bed before laying down next to her, almost like a pet. Maria wanted to be comforted while she felt her worst, while Shadow had no problem being that comfort for her. He was created to heal this girl. This purpose in life drew the two of them close, forming a strong bond.

But with that purpose in life for Shadow came its doubts.

Test after test, drug after drug, extraction after injection, all of it. He endured it. Maria deserved a chance at life just like everybody else.

Every failure in their experiments made Shadow feel like he was letting his best friend down. How can he be the Ultimate Life Form and not be able to formulate some form of cure for her as soon as possible? They felt like time was moving backwards on them and forwards on her, moving Maria closer to her fate while the Professor and Shadow were stuck at a crossroads with no solution.

Shadow sighed shakily with frustration, laying curled up with his spines down and his back against the girl's side. Maria weakly moved her hand to the top of Shadow's head and began to lightly scratch it to ease his tensions. She could tell Shadow was having a hard time recently with everything going on. However as he did his best to appear unbothered and stoic, walls built up high enough to never let anyone see weakness; she could see past it all.

The shaking sigh from the black hedgehog confirmed her suspicions. Shadow was definitely worrying about her. She was worried too, but not for her sake. She worried about Shadow's doubts in himself.

"I'll be okay, Shadow. Just need a day in bed."

"Get as much rest as you can. I'll be here for as long as you need me to." Shadow said in his curled up state, gently nuzzled against his favourite person like a loyal guard dog.

"Are you okay?" She asked softly, causing Shadow to twitch his left ear in response.

How could she be thinking of anyone other than herself right now?

"I'm fine. Just hoping we make some progress soon for you in our research."

"I heard it's been tough lately, but you and grandfather are doing your best." Maria muttered with a hint of positivity in her voice. "I have full faith in you two succeeding."

Shadow slightly nuzzled against her side more, almost like he felt the need to protect her. "But what if we can't figure it out in time? What if we make a cure and it's too late to save you?" He felt a tear forming in the corner of his eye, trying to mask his breathing as it began to get shakier with his words. Maria could hear his anxieties building.

Unexpectedly, Maria sits herself up as best as she can, slumping forward and wrapping her arms around Shadow in a weak but heavy hug. Shadow stiffened up in shock.

"Maria, what are you doing?! You're going to make yourself faint!" Maria did her best to keep herself upright.

"You and grandfather are doing incredible things for both me and the fate of humanity." She whispered weakly. "And if it's too late to save me, you still have the chance to help everyone else."

Shadow hugged the girl back and gently placed her back on the mattress to hopefully prevent her from fainting in his arms. He sat up on the edge of her bed and looked at her with worry.

"Maria, you're my priority here. We need to help you before we can help them."

"Shadow, I'm one person. There are plenty of-"

Before she could speak more, Shadow cut in, fear in his voice filling the room.

"I….need to. I need to save you." Shadow suddenly let a tear fall down his cheek, his breathing stiff as he tried his best to keep his composure around Maria. He knew he could be vulnerable around her. But he always hated thinking of being seen as weak and useless. "I don't want to lose you."

Ignoring Shadow's demands to rest, Maria tried to sit up again to hug Shadow one more time and help ease his pain. However before she could move too much, she felt her muscles giving in on her. She felt herself slowly inching towards the incline of her mattress before Shadow put his arms back around her, helping her fall back into her inclined mattress as softly as possible to prevent possible vertigo.

Maria smiled weakly as she made eye contact with Shadow again, her eyes starting to force themselves closed without her control from how exhausted she was. He placed a hand on hers and felt how cold she was.

"Please stay here while I rest. It calms me down." She whispered sadly. "And please don't doubt yourself so much. We love you and will love you no matter what happens. We're family."

Shadow sniffled slightly, wiping a tear from his eye as he tried to calm himself down. He moved himself closer to her, snuggling up against the girl again to protect and keep her safe, this time facing towards her for his own comfort. Maria placed a hand back onto Shadow's head, wrapping her arm around it to keep him close to her.

Shadow knew he and Maria had a long road ahead of them in formulating a cure for her sickness. But they found solace in knowing they both cared so much about each other. Shadow was more than just an experimental alien-hybrid to Maria. Shadow was her best friend, her pseudo little brother, her family. Beyond his rough exterior and monotone voice was a person that would go to the edges of the Earth to help someone. And Maria to Shadow wasn't just some sick girl. She was kind, taught him compassion and understanding. She brought out the best in him no matter what.

She was everything to him.

Once the two of them drifted off into sleep, Professor Gerald came in to take Maria's vitals. He looked at the two of them, a faint purring coming from Shadow as he comforted the girl. Gerald smiled proudly at the both of them.

"We'll figure out our next steps soon towards your recovery, sweetheart." He whispered as he watched over his granddaughter, taking her readings as quietly as he could. He glanced back at Shadow, noticing his ear twitch slightly as he slept.

"One day, there will be no more tests. No more days in bed sick. I promise you both."