Title: Interdependent Utility Function

Author: Supernerd3333

Summary: Relationship from an economist's point of view. S/YY

Warning: Very, very confusing.

I'd say this is one of the weirdest fic you'll ever see. I am taking an economic class. This idea just pops into my mind. Oh, well, see how you like it.

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Kaiba is driving home from Kaiba Corp at around 5 o'clock. Today he is on a mission. He is to make the most important deal he has ever made in his entire life. Deal? He smiled slightly. Only he would call this a contract. But then again, why not? He is a business manager; he knows all about economy. For an economist, this really is no different form a contract. As the thoughts take this interesting turn, he starts to wonder how Yami and his relationship fits economic laws.

Let's go back to the beginning of the relationship and look at the simplest model of economy. The price of good is determined by supply and demand. The point where supply and demand curve crosses is the equilibrium point, the point that indicates price and output. If the demand goes up and supply stays the same. The product will cost more. And trust him, the day when Yami first got his body, the demand for Yami's attention and affection skyrocketed. Some of the most prominent men and women seeked his love, or body. From another point of view, it's like a monopolistic competition. The products, in this case, the admirers, seek Yami, the buyer. Since supply increases everyday, but demand stays the same, Yami would get more of the admirers with less the price. But again, Yami isn't choosing at the equilibrium quantity either, which would be a high quantity. Yami only needs one person in his life and the others know it.

Kaiba didn't know whether they were chasing him for his look or for his fame. The only thing he knew was that although Yami wasn't short of admirer, he didn't go for any of them. Of course, that can be explained. If we consider Yami as the producer, or product for that matter, and the admirer as the buyers, then Yami has a monopoly since there is only one Yami. For all monopolies, they purposely restrict the products' production to increase price and profit, which could explain the reason he wouldn't go for the equilibrium quantity but only one person.

Kaiba was never one of the bluntant admirers. He tended to admire from afar. Any men who were not blind could see that the guy was gorgeous and wise beyond his years. But Kaiba was not the type to fall on his knees and beg for affection. Neither did he thought Yami would ever choose him. So Kaiba used the subtle methods of dueling. The challenges never ended. This way, he would never be seen as a quitter and this gave him a perfect excuse to see Yami. Until one day after a duel, he decided enough was enough and ravished Yami then and there. He still couldn't understand why Yami picked him though. He was always cold and rude, not mentioning constantly causing Yami great deal of trouble. But Yami chose him nevertheless. For that he was grateful. Never in his life had he felt as content as the moment he first held the boy in his arms. Now, this is not only a two way monopoly but also a two way monopsony, which means there is only one hirer in this relationship. Now everyone in the world knows that Yami is his and no one else's.

He smiled as reached a red light. Most people would scowl whenever they talked about monopoly, never realizing that they spent their entire life trying to form the perfect monopoly. Monopoly technically would decrease consumer surplus, which is the part where the buyer is willing to pay exceeds what is charged. But in this love monopoly, consumer surplus is maximized. He would do a thousand times as much to stay with Yami.

He resumed driving as the light turned to green. Another charge against monopoly is that it's difficult for new firms to enter. But in this case, he is grateful that this is the case. Like hell is he going to let some other guy come in and touch what is his. The last argument is that monopoly is not allocatively or productively efficient, which roughly means producer would not be producing at the level where it is most beneficial to society. For monopoly, the efficient way is that it produces more output. So is sharing his lover with, uhm, in his case, a thousands people, which is the socially optimal value, a great choice? Though it would benefit the "society" as a whole more? Didn't think so. It's times like this he is glad he is still cold towards others.

After they got together, they have down times. At times he wonder if the more time they spent together would mean less for both of them. Law of diminishing returns. He always hated that law. It means that the more people buy something, the less satisfaction they would get from it. This means that kids would only buy one of his duel disks and he can't hold tournaments continuously. Most importantly, this means Yami and him would eventually get tired of each other and break up. True, at some part of their relationship, they would argue and fight, almost to the point of breaking up. But they held together. The moment he saw Yami stuffing his things into a luggage bag, he knew he must stop his lover from leaving. He would take the boy into his arms and apologize his heart out. Yami would return the embrace and mumble against his chest. They would make up in the best way possible. Sometimes, Kaiba has to wonder if he lives just for those moments.

Over the time, they learned to manage their relationship better. They have an economy of scale. With the same amount of cost, they would get more output. Now, with the same amount of time, they would get more pleasure. And for a utilitarian, maximizing utility, or pleasure, is all that mattered. Since they are staying together, they must be maximizing their utility. That takes him back to the original question. Why does Yami like him? He could have anyone he wanted, why him? Kaiba shook his head as he pulled into the drive way in the mansion. He shouldn't be asking these questions. They are happily together now, and as corny as it sounds, he wants it to last forever. And he hopes that even though economic law states that in the long term, everything is a variable and will change, their love would not change.

And that's why he's here. He thought as he walked towards the room he and his lover shared. He squeezed the little box in his hands. Now, to make the 3000 years monopoly eternal.

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And there it is. I know I didn't really explain the economic theories that well, so if you have any question and you even bother to find out, email me and I'll see what I can do.

Have a happy Thanksgiving.