Ayato Kamina, a 17-year-old high school student, lives in Tokyo Jupiter oblivious to the world around him, having been raised to believe that the rest of civilization has been destroyed; but everything changes when a mysterious alien civilization invades his home.

Shinichi Chiaki is a first class musician whose dream is to play among the elites in Europe. Coming from a distinguished family, he is an infamous perfectionist; not only is he highly critical of himself, but of others as well. The only thing stopping Chiaki from leaving for Europe is his fear of flying. As a result, he's grounded in Japan.

During his 4th year at Japan's top music university, Chiaki happens to meet Noda Megumi—or as she refers to herself, Nodame. On the surface, she seems to be an unkempt girl with no direction in life. However, when Chiaki hears Nodame play the piano for the first time, he is in awe at the kind of music she plays. To Chiaki's dismay, Nodame moves into the apartment next to his and finds out that she is head-over-heels in love with him.

Moritaka Mashiro and Akito Takagi are pretty much foils of each other. Mashiro, an average 9th grade student but talented artist, and Takagi, an overall advanced 9th grader and aspiring writer. After great convincing, Takagi convinces Mashiro to join him in becoming the greatest mangakas Japan has ever seen. Takagi, with his gift of writing, hopes to become a successful mangaka, and Mashiro, with his gift of art, hopes to marry the girl of his dreams, Azuki Miho.

A former gang member wants to be Japan's best teacher. When he's hired to supervise a class of hopeless cases, it's his chance to prove himself.

The dark fantasy follows a high school sophomore named Akihito Kanbara. Although the boy appears human, he is half Youmu and invulnerable to wounds because he can heal quickly. One day, Akihito meets freshman Mirai Kuriyama when it seems she is about to jump from the school rooftop. Mirai is isolated because of her ability to manipulate blood, which is considered heresy among members of the spirit world. Disturbing events begin to unfold after Akihito saves Mirai.

High school student Chiyo Sakura has a crush on schoolmate Umetarō Nozaki, but when she confesses her love to him, he mistakes her for a fan and gives her an autograph. When she says that she always wants to be with him, he invites her to his house and has her help on some drawings. Chiyo discovers that Nozaki is actually a renowned shōjo manga artist named Sakiko Yumeno. She then agrees to be his assistant in order to get closer to him. As they work on his manga Let's Fall in Love (恋しよっ), they encounter other schoolmates who assist them or serve as inspirations for characters in the stories.