[Center][B]Kanojo ni Naru Hi[/B][/Center]
[Center](Day to Become Her)[/Center]

This is an interesting Gender Bender based in an alternate earth where this sort of thing happens to maintain a balance which is described below under "Emergence"

There are two story plots that revolve around two boys and their friends and how they handle this unusual problem

[Center]Kanojo ni Naru Hi[/Center]
[Center]Manga Cover Art[/Center]
[Center][IMG]http://www.anime-planet.com/images/manga/main_images/kanojo-ni-naru-hi.jpg[/IMG][/Center]

Kanojo ni Naru Hi 
[Hider=Miyoshi's Story]Description
Miyoshi is always competing and losing against his childhood friend, Mamiya, who is good at everything. One day, Mamiya collapses from illness and is hospitalized for several weeks. When he returns to school, it turns out he is genetically female, and has decided to try living his life as a girl now much to Miyoshi's horror.

(The Above paragraph is taken from the Manga's translator notes)[/Hider](5 volumes translated)

Kanojo ni Naru Hi Another
[Hider=Sagara's Story]Kanojo ni Naru Hi Another Manga Summary:
Sagara becomes a girl in his third year of middle school, and has to deal with his crush on Kurosawa, a female classmate
(The Above paragraph is taken from the Manga's translator notes)[/Hider]
 (5 volumes translated)
Thank you to Crimson Flower

[Hider=Emergence]The People of this Society Maintain a Fixed Male to Female Ratio. When there are few women some men change into women, it's a phenomenon much like happens to clown fish and is commonly called "Emergence"

There are tens of hundreds of cases each year but those that go through Emergence are usually young boys, it is rare for emergence to happen in the teens. When this happens the Emergence process burden is usually more than the body can stand so the mortality rate is high.[/Hider]

[Hider=Kanojo ni Naru Hi Review]Kanojo ni Naru Hi asks the modern question, "What would you do if somebody you knew switched genders?" 

But another strikes closer to the heart, "What if that masculine, male friend that you had always relied on, that friend who would do anything to make sure/help you succeed, that friend that would hide in the background and help you ask that girl you like out--what would you do if that friend went from an alpha male to a soft-skinned, beautiful female?"

In Kanojo ni Naru Hi, the author, Akane Ogura illustrates the struggles of a young man named Miyoshi, who is conflicted as to how to deal with his (now-evolved female) best friend. The one friend--and person--he most looked up to as a man, has become a woman. "Do I treat her like a woman, or like a man like I always have?" Stuck between personal desires and social correctness, Miyoshi is stuck at odds as to how far he should go for his friend. 

Equally conflicted is his best friend, Mamiya, who now must live life with the body of a girl. In a new world as a seemingly much more vulnerable human being (having once been accustomed to the strength of a man), Mamiya doesn't know how to deal with being a woman, resulting in an internal turmoil of feelings that she cannot explain or understand, both to herself and Miyoshi.

As one reads this gripping, fast-paced manga, one begins to wonder if this is in a way, a propaganda manga in which the author is trying to vouch for acceptance of Transgender Women and Men, or if this was merely an experience the author had felt that she wishes to portray within this manga. The struggles

Whatever be the case, this manga is a worthy read. With every page turned within this manga, the desire to receive the mysterious answers to our own, modern questions only grows stronger and our thirst grows deeper. Every page is filled with thoughts, with underlying meaning that can only be groped once read. And when the chapter ends, our hearts and minds groan out and desire for more--only to be filled with endless, seemingly unanswerable questions, with our minds and eyes always seeking the answers in the chapters ahead.[/Hider]

Now to why I've bored you with all the above information;"Naturally I'd like to do a twist on this story"

"How Twisted?" You ask

Not so much that it couldn't all happen in the threads.

They've done the Boy becomes girl meets Boy. 
Boy becomes Girl meets Girl who was once a Boy.
So I propose the next plot be a Boy meets Girl and becomes Girl (Kinda Kashimashi)

Now in my plot this will become a Gender bender Yuriesque plot.
The Boy and Girl will be in the beginning of a romance that's been building since they first met in junior high. They live on the same street and were Besties before they began to realize that they loved one another. 
The Boy comes from a broken family his parents having divorced and he lives with his mother.
The Boy and Girl are enjoying their first kiss when the Boy collapses and has to be rushed to the hospital. He disappears for three weeks. And his mother calls the girl saying that he's going to be released in a week an asks if the girl would like to visit her best friend in hospital.

That's the general story beginning and we'll likely need to play it out a little before the hospital to get a feel for our parts. After the hospital we'll be in uncharted territory and the free forming will begin.

I'd like to play the part of the Boy turned Girl but can flip to the other role with a little convincing.