SaiKano
Saikano, also known as She, the Ultimate Weapon (最終兵器彼女 or Saishū Heiki Kanojo) is a manga and anime (animated) series by Shin Takahashi (高橋しん, creator of IIHITO. and Your Fragment). Saikano was originally serialized in Shogakukan's Big Comic Spirits magazine.
Story
This anime, as suggested by the sub-title "The Last Love Song On This Little Planet", is primarily a love story. Although war is the backdrop for the show, we are not drawn into the war by extravegent battle scenes, or the intricate details of national politics. The story focuses primarily on Chise's reactions to her increasingly powerful destructive abilities, Shuji's reaction to the same, and the relationship between the two of them.
A number of minor characters, who do not necessarily know of Chise's role in the war, have sub-plots that mostly concern everyday people in the context of war: a woman whose husband is constantly away from home, a school boy who joins the army to protect his sweetheart, a girl whose civilian boyfriend was killed in a bombing, and others.
Shy Chise and nervous Shuji are high school seniors in a small town. They have just started dating. But everything changes when Shuji discovers that Chise has been engineered by the Japanese Self Defense Force into the Ultimate Weapon!
What do you do when the girl you love becomes a weapon of mass destruction?
IN JAPAN
SAIKANO, the anime series by Gonzo Digimation, aired on Family Gekijo July 2, 2002, on CBC and continues to be broadcast throughout Japan!
SAIKANO, the manga, was first published in Japan in Shogakukan's BIG COMIC SPIRITS in 1999 up to October of 2001. Big Spirits Comics SAIKANO (consisting of 7 volumes) sold over 2 million copies in Japan!
CHISE
High-school senior, like Shuji. Shy and timid (with a tendency toward clumsiness), Chise is often breaking into tears and apologizing for everything she does. After asking out Shuji as a test of courage, the two quickly fall in love. For reasons unknown to either of them, Chise is one day transformed by the military into a weapon. The more battles she fights, though, the more she feels herself becoming more weapon than human.
SHUJI
High-school senior and former member of the track team. Above-average grades, but a little cold and distant when it comes to personality. Having had at an early age an experience with what he thought was "love," he's confused as to what "love" should really be.