Basically I wrote this during a pain flare of my own and it is 100% based on my experiences of that. I also rather enjoyed what would happen if Hotch was there to look after me during a flare because I'm a sad lonely loser, so I wrote this one shot. I stole the title from sherlock but nothing else. Synesthesia for pain, and graphic pain descriptions hence the T rating

Pain is coloured pink. Fluorescent pink like a highlighter, it flashes behind eyelids and stains her dreams. She can taste it on her tongue, rolling around like a hard boiled sweet, the sour edges bringing tears to her eyes. Sometimes all she can do is lay in bed and allow the pink to engulf her. Times like that the pink is so bright it hurts to see, like looking at the sun. Blinding, and debilitating. Other times she can soften the pink, let it mellow to a semblance of pastels, can see her friends, live her life like she used to.

161 days since she was stained pink.

161 days since she had a day without pain killers, without calculations and planning.

161 days since she was normal.

Today was a hot pink day. She was curled up in bed, the heavy comforter weighing on top of her keeping the racing thoughts at bay. She squeezed her eyes shut, envisaging the pain as a canvas, a paint roller painting over it in ice blue. A quiet groan passed her lips, as she hugged the pillow closer. She didn't open her eyes as he walked into the bedroom, the whisper of his trousers and his gentle footsteps giving her an idea of where he was in the room.

A hand softly stroked her hair off her forehead, followed by a kiss.

"How bad?" his voice was barely above a whisper, filled with care and concern.

"Si-i-ix" if her voice hadn't cracked, he might have believed her.

"Your heat pack is heating up on the bed next to you, and your pain killers are on the side table with some water. I'll call at lunch time, OK?" He pressed one more kiss to her sweaty forehead and left, a soft "I love you" floating through the room as he gently snipped the door closed. She curled back under her covers, trying to take deep steady breaths.

You're OK, You're OK, You're OK

When the heat pack stopped bubbling and alerted her to its completion she carefully rolled over and took it off its charging port. Holding it close gave her a modicum of relief, reducing the anger of the pain. It took 10 minutes before she could open her eyes, a further 15 before she had built up enough energy to grab the painkillers from her bedside table. She hated the small yellow and green capsules. They helped her with her pain but were the reason she got dirty looks from pharmacists and doctors, the reason she hated seeing new medical professionals. They all thought she should be using something else. Unwilling to continue prescriptions, not wanting to support her habit.

They had argued, the fight she had held multiple times, with multiple doctors. Nothing else worked. Nothing else helped. She could usually convince them to listen to her. They would write the prescription begrudgingly, handing it over with warnings about the addictive qualities, and maybe she should try some mindfulness. What they would not do however was investigate the reasons. She had argued until she was blue in the face, seen so many doctors and so many hospital visits trying to find a reason. They would rather give her pain killers than order scans, would offer counselling before they would offer specialist appointments, and she was tired. Tired of fighting with insurance. Tired of fighting her doctors, Tired of fighting her pain.

The pink was fading at the edges by the time he called. She hadn't realised that much time had passed, too caught up in the abyss of pain and thought spirals.

"Hey you, how're you doing?" He was worried, he always worried on days like today.

"Been worse, I might be able to nap soon"

"I'm glad, you need to rest when you can babe" he sighed down the phone, it sounded stressed. She knew what that meant.

"You've got a case" it was a statement, no accusations. They had danced this dance too many times to be upset by it.

"It looks like they need us in Ohio, a ritualistic unsub, but the body disposal is sloppy and careless. Hopefully, we can find some forensics"

Her heart sank, she hated missing cases, and hated being alone during flares even more. Not for the first time she cursed her body, tears springing unwanted to her eyes.

"I'm going to miss you" she said, a hand stroking her blanket as she fought to keep her voice even. If he thought she was in too much pain he wouldn't go. Wouldn't be with the team, and they needed him.

"Me too babe, I'm about to get on the jet but I'll text you as often as I'm able to, OK?"

"Sounds good, stay safe yeah? Love you"

"Love you too" with that he hung up. She scrubbed at her eyes, careful not to move too much lest she aggravate the pain. With a sigh she slowly settled onto her side, piling pillows around to hold her in place. By the time she had managed to create a solid position on the bed her eyes were sagging in exhaustion. She let them drift closed, painting over the pink repeatedly until she finally fell asleep.

She was woken by the pain, it was the brightest it had been in weeks, stabbing into her with no mercy, no relief. Gasping she clutched at the bed sheets, balling them up in her fist as she tried to focus on anything except the pain. Attempted to swallow the bile making its way up her throat. It was excruciating, sobs were tearing through her throat without warning, sweat pooling below her body. She grabbed her phone from beneath her pillow, the pink tinging the screen and forcing the keyboard to shimmer before her eyes. She sent a text, pressing send as the pink began to fade to black at the edges. Someone was yelling, she didn't know who, but the room was spinning too much for her to notice. Quickly, the black overcame the pink, she had one moment of dark cool relief before she knew nothing. She was floating in a void, able to finally breathe.

He checked his phone, she had been sleeping, so hadn't replied to any of the messages he'd sent throughout the day, it was nearing evening now and the sound of a text was welcomed. However, as he read the screen panic took over. He never thought a single word text could affect him this much.

Ten

He read the word again, hoping if he stared hard enough it would change. She hadn't been at a ten in weeks, and when she had she wouldn't admit it. He stood up from his seat, his long legs running from the conference room before he knew where he was going. Someone was following him; he couldn't know who but with a quick explanation they let him be. As he drove to the airport, he ran through the list of people to call. She hadn't been picking up her phone since sending the text and panic was rising within him. He called the only person he knew would be able to leave their desk that very second.

"Garcia, I need you to go to my house, it's…it's Casey. I don't know what's wrong but she's saying it's a ten. Its bad, please, I'm getting a flight, but I need somebody to be there now"

"I'm leaving the office this second Hotch, I'll drive at the speed of light. Have you called 911?"

"No not yet I don't know if I need to. Let me know what's going on and I'll make the call"

As he pulled into the airport, he abandoned the car at a valet station. The team would get it later. He was running with a go bag in hand, thinking it through. He knew she likely physically needed the hospital, but the last time she had been in hospital her mental health had declined so rapidly it had done more harm than good. Hospitals were draining for her, the amount of self-advocacy she needed, and the arguments they had had with medical providers weren't worth the medical care she received. Unless it was dire, he wanted her to stay at home where she could relax and recover as much as possible.

He handed a credit card to the agent at the ticketing booth, a flight was leaving in 45 minutes. Thanking his lucky stars, he raced through the TSA checks towards the gate. As his feet slapped off the linoleum floor his phone rang, it was Garcia.

"Sir, I'm here. I don't know what to do! I tried shaking her shoulder, but she just mumbled something and wouldn't even open her eyes!" Garcia was panicking.

"In the kitchen there's a first aid kit, there's a couple of pre-filled syringes in there. I need you to get one and give her half a syringe. Do you know how to put it into a vein?" He had procured the morphine the last time she flared up this bad, an old friend giving him information on how to administer it safely, a secret between the pair.

He wanted nothing more than to be with her, his worries were beating a staccato against his chest, and he knew they would not rest until he could see her. Instead, he had to listen as Garcia gave her the medication, praying it would be work, that she would be OK.

"She's relaxing a little, I don't know how much it's helped but she's breathing kind of normally now?"

"Thank you Garcia, I'll be there in a couple of hours. Keep an eye on her, if she comes to, she might be disoriented, just explain what happened. Tell her, tell her I love her and I'm coming" He closed his phone and leant back against the seat. He had boarded the plane on autopilot, too concerned about Casey to pay any attention to his surroundings.

The void had changed, taking on an orange hue, blurring together like the void was trying to fight back, it wanted to be in front but didn't quite know how. She liked the orange, it felt more friendly than the pink had ever been. She felt like she knew the orange from somewhere, but she couldn't quite place it. It was warm in the orange, safe. She let it pull her close, wrap her in its arms and stroke her hair. She could only see orange now and she liked that, the orange was melting into her, like butter in a pan. She could feel it dripping through her steadily painting everything it touched.

She lay back and watched the orange for what could have been minutes or years. It was both over too fast and never ending. But eventually the orange began to change, as if a sunrise were breaking streaks of pink began to make an appearance. Whisper thin threads working their way across her eyelids. As they curled around her, she began to feel her limbs reattaching themselves. The pink was growing and picking up speed. The more she could feel her body the more pink she could see.

There were arms holding her, and she could hear them saying things, but the orange and the pink were fighting, and she couldn't hear much above the pounding of their fists in her ears.

Slowly the orange admitted defeat, as it slunk to the outskirts of her vision she could hear his voice more clearly, she knew who the arms were now.

"Thanks Spencer, let me know once you have a list of brothers who served in the military together, and get Morgan to take Prentiss to the morgue." He gently tossed the phone onto the bed - she could hear the muffled thump of it landing on the comforter. His hand was stroking her hair and it felt nice.

The pink was getting stronger, and she longed for the orange to return. A soft cry parted her lips as she remembered the orange.

"Casey? Babe? Hey, hey, you're OK, you're alright. I've got you, you're at home. You're waking up, you were out for a while" He was whispering, pressing kisses to the top of her head as she struggled to open her eyes.

After a short time she managed, blinking at the light shining behind the curtains. Her head was lying against Aaron's chest, warm and solid – it was comforting. She knew when she had him, she wasn't alone with the pain. She opened her mouth to say something her mouth so dry all that came out was a croak. He handed her a glass of water, holding it against her lips for her when her hands shook too much to hold it herself. After taking a few sips her mouth felt more normal. She could feel it cooling her throat as it flowed down, it had obviously been a while since she drank anything.

"What happened?" She tried to focus on his voice as the pain howled inside her, listened to him explain that she had experienced a flare and that Garcia had given her morphine while on the phone with Hotch. She had been out of it for hours, Hotch with her for at least 2 of them.

"That's what was orange?" She asked, a hand coming up to rest against his chest as she tilted her face to look at him.

"What do you mean love?"

"It was black, and it was nice because I wasn't sore, but it was dark, and I was cold. Then everything went orange. I liked the orange"

He looked a little surprised but nodded his head. "I think that was the morphine. Do you-" he cleared his throat "do you see colours for other things? Like what colour am I?"

She closed her eyes and thought about it. "You're the colour of honey, but a darker brown type, almost a whiskey kind of hue. I can't do it with everything though. I thought it was only the pain I could see…"

"What colour is it?"

She knew what he meant, knew what it he was referring to. The it that was currently trying to pierce its way out of her body, angry at being held inside for so long. She wanted to cut it out of her, dig until she had scooped every last droplet of pink out of her body. Never to be seen again. But he was holding her, and when she was with him the pain was minutely easier to manage. She could gain a fraction of an inch of control.

"It's pink, my pain is pink"