Spencer was unfamiliar when it came to being affectionate. Of course, he knew of the word and what it meant, but he could not, for whatever reason, physically comprehend it. Spencer was unsure how to be affectionate. A absent father and ill mother taught Spencer early on that it was less painful to hold people at a distance, especially the ones you loved most. And there was no one Spencer loved more than Derek.
Derek made him happy. He had the uncanny ability to make Spencer feel like he was wanted, even at the lowest points throughout his life. Derek would smile with those beautiful eyes and perfect mouth, and Spencer would gladly return the gesture. Affection came with ease to Derek, he knew exactly what to do, and Spencer was left struggling behind him, flailing his arms in an attempt to swim. This made their relationship difficult.
The only thing Spencer lacked more than the ability to be affectionate, was communicating on an emotional level. Derek felt ignored, like he was missing something, and Spencer couldn't remedy the situation threw knowledge alone. This frustrated Spencer almost as much as it hurt him. This was not how he wanted life with Derek to be like. Spencer decided the only way he would ever learn would be through observation, and so he set out to do exactly that.
Observing affection was not as easy as he presumed it would be. There were many different categories for affection to take place: families, friends, and romantic interests all involved varying types of affection. The way Penelope interacted with people was mostly the same, but there were subtle differences. The way she hugged Derek was slightly different then the way she hugged Kevin. Spencer took a lot of mental notes.
Like how Aaron's gaze softened when he talked to Jack, no matter what setting. JJ, while keeping her hands to herself under any situation, would pick Henry up to cuddle him, or asses any cry he might emit. Derek would gently place his mothers hand in his own when they would sit and talk, but would often grab Spencer's arm towards him when he thought the other man might come to harm. Dave's tone of voice dropped to a soft one when he was speaking to someone he was fond of, and Emily would subconsciously trail her fingers down the person she was talking to arm to indicate that she was there with them. Spencer had facts, and broken fragments of what being in a relationship should be like.
Observations complete, Spencer set out to try some of these newly acquired "techniques". The only problem with that notion was that Spencer knew the "techniques", but not the proper time in which to apply them. This ended in a few bad experiments he'd rather not mention. These failed experiments, however, alerted to Derek that something was amidst. The conversation that resulted was not a comfortable one, but very much needed.
"What's wrong? And before you try to say nothing, let me already state that I won't believe you," Derek spoke lightly, but ultimately concerned for the others well being.
"I don't...know how to do this," Spencer struggled, sitting on the edge of Derek's bed, hands falling to his knees with a rather loud sound.
"Do what, exactly?" Derek questioned, sitting beside Spencer and taking a hold of his hand, peering deeply into his eyes.
"This! What you're doing right now. You always know what to do to make me feel better. Someone cries, you know what to do. When you want to be closer to people, you know just how to touch them. I just want to be able to do that for you."
"Do what?"
"Show you how I feel."
"Spence, it's nothing I think about. I just do it. If you listen to your body instead of over thinking it, this sort of thing just happens naturally. It shouldn't be forced." Spencer mauled over that last statement for hours after that conversation had ended. Days later, he was still thinking about it. That, he decided, was exactly the problem. Spencer spent every minute of every hour thinking. For once, he decided to try and look at something, not as a analytical thinker, but as an emotional being.
Misinformation had led JJ to believe that Henry was severely ill when he wasn't. Instead of rambling on in an uncomfortable state, Spencer embraced the fearful mother, telling her that everything would be alright. This was a different experience for Spencer, allowing him to be apart of the situation instead of merely observing it from an outside perspective. Spencer grew more and more comfortable with his progress, but still faced a concerning problem. Spencer still couldn't be affectionate with Derek in a so-called "normal" manner.
This changed one day, however, when they were walking down a busy street, and Spencer marveled at all the people there were on this planet. Of course, he knew the exact number, and knew the amount of people present was no comparison to the actual figure, he got to thinking. They could have gone their entire lives not knowing that the other existed. This made Spencer pause mid step, throwing Derek's pace off as well. Derek looked at Spencer oddly, silently asking him what was wrong. Spencer merely smiled, shaking his head as he laced their fingers together in a silent gesture to tell Derek that nothing was wrong with just a simple touch. A touch he hadn't thought about, but felt.