Yukino Miyazawa is the female representative for her class and the most popular girl among the freshmen at her high school. Good at both academics and sports on top of being elegant and sociable, she has been an object of admiration all her life. However, in reality, she is an incredibly vain person who toils relentlessly to maintain her good grades, athleticism, and graceful appearance. She wants nothing more than to be the center of attention and praise—which is why she cannot stand Soichiro Arima, the male representative for her class and the only person more perfect than her. Since the first day of high school, she has struggled to steal the spotlight from her new rival but to no avail. At last, on the midterm exams, Yukino gets the top score and beats Soichiro. But, to her surprise, he congratulates her on her achievement, leading her to question her deceptive lifestyle. When Soichiro confesses his love to Yukino, she turns him down and gloats about it at home with only a hint of regret. But the very next day, Soichiro visits Yukino house to bring her a CD and sees her uninhibited self in action; now equipped with the truth, he blackmails her into completing his student council duties. Coerced into spending time with Soichiro, Yukino learns that she is not the only one hiding secrets. [Written by MAL Rewrite]

Sentan Island is a small island surrounded by the Yuden Sea. It exists in a state of dreamlike tranquility, cut off from the war between the Northern Government and the Southern Continent Free Zone. Our hero, Akiyuki Takehara, lives on Sentain Island along with his mother Fusa. He is currently separated from his father, the town doctor Ryuzo, but the bond between father and son remains. One day, after taking Ryuzo the lunch that Fusa has made for him as usual, Akiyuki arrives at school, where he is caught up in an explosion along with his friends, Haru and Furuichi. The explosion produces a mysterious light, which enters Akiyuki's arm, causing him excruciating pain. He's given no time to understand it, however, as the white-haired girl who rode on the bus with him guides him to a power unlike anything he's ever known.

The Edo period of Japan gave rise to a clan of warriors with a very specialized, magical skill. The clan was known as the Manyuu, and the skill was the ability to administer a sword strike that could shrink the size of a woman's breasts. This might not seem like an ability that could exert power over a land, but in Manyuu Hikenchou, large breasts denote status, wealth, fame, and influence. Grave concern has arisen in the Manyuu clan due to the actions of their chosen successor, Chifusa. Disgusted with the breast obsessed society that the Manyuu have created and perpetuated, Chifusa has not only deserted the clan, but also stolen the sacred scroll that details their techniques to growing and severing breasts. Fortunately, Chifusa is not completely alone. Her fellow warrior Kaede is sympathetic to her cause; a sympathy that could place her in considerable danger. Now wanted by the very clan that raised her, Chifusa must defend her life and Kaede's while seeking to undo the damage their brethren have done to the land. Along the way, Chifusa will discover that she harbors a power that goes far beyond the scope of her training, one that could help shape and change the land that she seeks to bring equality to.

Keitaro Urashima promised a girl when he was young that they would meet up again at Tokyo University in the future. Sadly, in the National Practice Exam, Keitaro ranked 27th from the bottom. Knowing his grandmother owned a hotel, Keitaro intended to stay there while continuing his studies for Tokyo U, only to find out the hotel had long been transformed into an all-girls dormitory. Through an odd twist of fate, Keitaro eventually became the manager of the dorm, beginning his life of living with five other girls.