Waking up to an empty bed was something Derek had gotten used to when he was spending the night with Spencer. Never fail, he'd roll over in the middle of the night and his hand would hit the empty half of the bed. When the job really started to get to Spencer, his insomnia would kick in, and considering his fear of narcotics, he wasn't keen on taking any medications, even if it meant he could sleep at night. Most nights, Spencer would be in the living room, reading a book or attempting to straighten his books in a new order. Sometimes, he'd even get out of bed and just sit out in the kitchen, content with the silence around him. It was never weird to him, because everyone handled the job differently: Derek himself would go to the gym to work off any aggression or negative feelings about a case.

One night, he woke up to the sound of footsteps on the roof of his house. He sat up in bed, wondering what the hell was going on. Then he looked over at the other half of the bed and he knew: Spencer found a new place to spend his sleepless nights. Usually, he'd let Spencer work things out for himself, but tonight just felt different. Pushing the blankets off himself, he pulled on a sweatshirt, grabbing a blanket from the closet and slipping on his sneakers, walking out to the backyard. He saw a ladder propped up against the side of the house and smiled to himself before putting the blanket over his shoulder, climbing up.

Spencer was sitting with his legs crossed underneath him, staring up at the stars above him. He wasn't wearing a sweatshirt and was just sitting there in his t-shirt and sweatpants. Derek carefully stepped forward, wrapping the blanket around him and sitting down, wrapping his arm around him. Spencer gave him a smirk before pulling the blanket tighter around his body.

"Thank you."

Derek nodded. "What brings you up here?"

"I couldn't sleep, I'm sorry if I woke you."

Derek shook his head. "It's fine. Now, what brings you up here, of all places? I'd think you'd be downstairs, arranging your books or re-organizing my refrigerator."

He gave him a quick shrug. "I did those earlier this week. Something about coming up here just felt right."

"So you took the ladder from my garage, put it against the house, climbed up, and found the most comfortable spot on my roof?"

"…That sounds about right."

"Can I get you anything? Some coffee, a notebook, more blankets?"

Spencer thought to himself before nodding. "Can you grab me my journal from my desk, a pen, and a cup of cocoa, if it's not too much trouble?"

He leaned over, kissing Spencer's cheek. "I'll be back in a minute."

Spencer gave him a nod, keeping his gaze upward.

Derek gathered up the things Spencer asked for, along with a few extra blankets and some pillows. He threw them all in a bag and stacked two cups of cocoa, carefully climbing back up the ladder and sitting next to Spencer, handing him a cup.

"What's all this?" he asked, motioning toward the bag.

"I figure if we're going to be up here for a while, we might as well get comfortable."

Spencer arched an eyebrow. "We're? Derek, it's my bout of insomnia, not yours. You should get some sleep. We have work in the morning and both of us shouldn't be overdosing on caffeine tomorrow."

He shrugged, setting the pillows down and lying down, resting his head against one of them. "I'm awake, you're awake, we might as well be awake together."

"But Derek-"

He reached up, putting his hand over Spencer's mouth. "No 'but Derek's."

Spencer shoved his hand off. "You don't need to do that to keep me quiet."

"Well, your face is too far away for me to go to my other method," Derek reasoned.

He smiled slightly, taking a sip of his cocoa and sitting beside Derek, pulling a blanket over him.

"So what are we doing tonight?" Derek asked, motioning toward the journal.

Spencer tapped his pen against it. "I don't know, this is the time when my head is clearest, and I can actually write down everything that's on my mind."

"Do you want me to leave?" He knew how private Spencer was about his writing and didn't want to make him feel uncomfortable.

He shook his head, clicking the pen and starting to write. "You won't distract me."

He watched as Spencer wrote down what he suspected to be everything he was currently thinking about. The pen had hit the paper and Spencer started writing, not seeming to stop anytime soon. He watched him cross his t's and dot his i's, and smiled at the look of pure concentration on his face. He only took a break to sip his cocoa, then set it down beside Derek and keep writing.

Derek felt himself falling asleep when the pen clicked again, Spencer sticking it inside the journal. He set it down on the roof before turning to Derek.

"If you want, you can go back inside. You don't need to stay out here with me all night."

Derek shook his head, rubbing Spencer's arm. "It's fine. It's kind of nice out here."

"Derek, it's the middle of winter and it's probably about forty degrees."

He shrugged. "Then I guess you should get under these blankets and keep warm, and in turn, keep me warm, because you're my little space heater."

"You're really suggesting that we cuddle on the roof?"

"…We've cuddled on the jet. Let's be honest, this is probably a lot more comfortable."

Spencer gave him a look before deciding to just cave in, lying down beside Derek. He rested his head on Derek's chest and looked up at the stars above him.

"Tell me what you're thinking down there, Pretty Boy," Derek whispered, running his fingers through Spencer's hair.

Spencer smiled at the nickname, pointing up at the stars. "Sirius is visible tonight."

"And who's Sirius?"

He pointed to the brightest star. "It's also known as the dog star."

"Did you make a wish on it?"

He shook his head. "The likelihood of a wish on a star coming true-"

"Have you ever tried?"

"Not exactly, no."

"Then you can't talk it down. Now come on, keep it in your head and wish for something."

"Derek-"

"Go on."

Spencer rolled his eyes, looking up at the star then closing his eyes, thinking to himself for a minute before opening them again. "Satisfied?"

"Very."

For the next hour or so, Derek let Spencer talk about anything that his heart desired, whether it be the stars or a documentary he saw on TV the previous week when he couldn't sleep. At one point, Derek reached down, rubbing his arm.

"What about that one, Spencer?" he asked, pointing to another star. "What does that one mean?"

When there was no response, he raised an eyebrow, looking down at him. "Spencer?" He then noticed that for the first time in a while, Spencer looked extremely comfortable, fast asleep and his head against Derek's chest. Rather than moving him, Derek opted to stay up there, reaching over and setting an alarm on his cell phone. Though it was cold, Derek had to admit, something about this was comfortable – it had to be if Spencer was finally able to get some sleep at night. He pulled the blanket over them before wrapping an arm around Spencer, pulling him closer and kissing the top of his head.

This was the first of many nights where Spencer ended up on the roof as a result of his insomnia, but that night had been the last he'd gone up there alone. Every time, he'd wake up Derek to keep him company, and he never minded. Though he could never fully cure Spencer's insomnia, he enjoyed being the person to help it go away, no matter how temporary.