Just a little ficlet from The Alien Parasite Hypothesis, an episode I hated at its first airing and adore now, largely due to my growing love for the Shamy. So here's a bit in Sheldon's mind, explaining why he felt jealousy over Amy's attraction to Zack – my take on how that's possible even for a man like Sheldon.

I don't own anything.

"Is it possible that your concern for me at this moment is motivated by nothing more than simple jealousy?"

It was a simple question, as simple as the jealousy that Amy had referenced. It was an easy question, one that, if asked at any other time in his life, in any other situation, would have been an easy, truthful answer, a simple "Of course I am not jealous." He wasn't sure if she intended it to be as difficult a question as it seemed.

Maybe it was the way she had asked it.

Maybe it was something else. Either way, he didn't know how to answer her.

"I hadn't considered that. Give me a moment." He paused briefly. "All right, I've considered it."

"And?"

Sheldon kept the same face that he always showed the world. "And I reject it."

"Do you reject it because you don't feel jealousy, or because you are suppressing jealousy?"

He hated that she had asked that question. He hated it because he didn't like to be challenged. He hated it because he didn't want to lie to her, but the truth was too confusing and terrifying to him to admit.

So he went with the safe option.

"I think I'll eat my lunch at home."

And with that, Sheldon was gone, taking first the brains that Amy was cutting with such an imperfectionist's hand that it was almost embarrassing, then his actual lunch, and heading for the door. He had never wanted to leave anywhere so quickly, at least not someplace that didn't have too many germs, too many people, or too many people fornicating without the courtesy to keep it down.

And he had never been afraid of an emotion before. The emotions that he would feel would not necessarily be easy to control, but they were emotions that were perfectly acceptable to express in public. Fascination. Anger. Sadness too, but only to a certain extent, and that's what his bedroom was for, for crying. His bedroom was where he headed now.

His beautiful mind, boasting an I.Q. of 187, didn't understand what he was feeling right now. Actually, that wasn't totally true. He knew what he was feeling, and he understood why. And here, in his room, he could be completely honest with himself.

He was jealous. And it pained him to admit it. Amy was attracted to Zack and not only did he not like that, (it scared the Hell out of him that someone that was so much like him was changing; he'd just found someone that he thought had her priorities straight with the intelligence to back it up, and here she goes, proving that she's just like all women) he was jealous of that fact.

Sheldon cocked his head. Did he just admit that he wanted Amy to be sexually attracted to him?

He thought about it for a long time before deciding that no, in a perfect world, Amy Farrah Fowler would not have sexual feelings for him. But she wouldn't have them for Zack Johnson either. She would be like him, lacking carnal feelings for anyone. They wouldn't have to worry about anything; they could continue as they were without being distracted from their friendship and their work, which was more important than anything else.

But if Amy had to be sexually aroused by someone, why wouldn't it be him, Sheldon Cooper, B.S., M.S., M.A., Ph.D., Sc.D., who was more in common with her than anyone else either of them had ever met? Why Zack? Was she attracted to the muscular, primitive type that also gained the affections of girls like Penny? If she had sexual feelings for Sheldon it didn't mean that they had to do anything about it. They were intelligent; they would have worked through it together without having to engage in any of the activities that Penny and Leonard would have. With their similarities and their connection, was it really so wrong to wonder why the person that Amy had those primitive feelings for wasn't him? People like them didn't just get those feelings; if they did get them wouldn't it be logical to have them for someone like them and not just for anyone?

Maybe Sheldon wasn't jealous. Maybe he was just confused. Maybe he just wanted to know why.

Sheldon decided that the only thing to do was to contact Zack Johnson and arrange for him and Amy to meet. Maybe if they acted on Amy's primitive emotions she would stop having those feelings and return to Sheldon and be the person that he thought she was; the fellow beautiful mind who looked at the world in that special way that most people were incapable of achieving. Maybe then he'd have the regular Amy back, the Amy who was his friend, his intellectual equal (though he'd never admit it to her or anyone), and his platonic partner.

And that was all he wanted. He'd always had one or two friends, but this was different. Amy was his partner. Not in the way that Bernadette was Howard's or Penny used to be – and still could be – Leonard's. But she was his partner nonetheless. And yes, she was to him as Bernadette was to Howard and so on, but they were still different, and when they came into contact with each other Sheldon realized that a little part of him had always felt alone, and meeting Amy proved that you really didn't know what you had until it's gone. Until very recently, that little bit of loneliness was gone. But now it was back, because he didn't know if he'd ever have the same relationship with Amy again. He wanted that completeness.

And honestly, right now Sheldon would trade a Nobel Prize to have it back. But he'd never admit that to anyone, either.