Michi and her family have just moved into the Happiness House, a huge tree with all sorts of little buildings and houses built on and inside of it. Upon exploring what is to be her new bedroom, Michi finds an odd nut-like object. Before long, a strange creature, Nanami-chan, hatches out of it. The two become fast friends. Together, Michi and Nanami-chan learn all kind of new things, and everyday they meet more eccentric residents of the Happiness House. (Source: ANN)

Departing from their respective hometowns, two young women with identical names are brought together in their pursuit of new beginnings. With their hearts set on going to Tokyo, Nana Komatsu dreams about blissful love, while Nana Osaki aims for a successful music career. The former has a cheerful and friendly nature, but her naivety has steered her romantic life astray until she meets her dependable boyfriend—Shouji Endo. Without letting herself be dismayed by Shouji's decision to study in Tokyo, Nana works hard to earn enough money and follow him there. Meanwhile, her namesake is a solitary punk vocalist whose impassioned romance with her band's bassist, Ren Honjou, comes to a sudden end. Though heartbroken, Nana bravely looks forward and travels to the capital with the ambition of becoming a recognized artist. Shortly after they arrive in Tokyo, the girls cross paths again due to an unexpected coincidence that ultimately leads them to live under the same roof. As they grow closer, the two strive to support one another amid their struggles to forge a future for themselves.

Michi and her family have just moved into the Happiness House, a huge tree with all sorts of little buildings and houses built on and inside of it. Upon exploring what is to be her new bedroom, Michi finds an odd nut-like object. Before long, a strange creature, Nanami-chan, hatches out of it. The two become fast friends. Together, Michi and Nanami-chan learn all kind of new things, and everyday they meet more eccentric residents of the Happiness House. (Source: ANN)

In 2099, Earth has shifted off its axis and begins to rotate at an angle of 90% to the 20th-century equator. Three years of natural disasters follows, and when things settle down, Earth's ten billion population has died and only two million moon colonists remain. Some return to begin the repopulation of the world in seven new cities and the remaining colonists of the moon fear that their former neighbors might pose a threat and construct a ring of defensive satellites to trap them on the newly repopulated homeworld. (Source: AniDB)