Kouichi Sanada and Kazuki Aihara's childhood friend Mao Mizusawa has returned after living in France for a couple of years. Kouichi is surprised to learn that, since her parents are remaining overseas for the time being, his mother has agreed to let Mao stay with them. The three friends help each other deal with the ups and downs of high school romance.

Seiya Kanie, a smart and extremely narcissistic high school student, believes that the beautiful but reserved Isuzu Sento has invited him on a date at an amusement park called Amagi Brilliant Park. Much to his chagrin, not only is the location a run-down facility, the supposed date is merely a recruitment tour where Sento and Princess Latifa Fleuranza, the owner of the theme park, ask him to become the park's new manager. Their cause for desperation? As stipulated in a land-use contract, Amagi has less than three months to meet a quota of 500,000 guests, or the park will be closed for good and the land redeveloped by a greedy real-estate company. Seiya is won over by the revelation that Amagi is no ordinary amusement park; many of its employees are Maple Landers—mysterious magical beings who live in the human world and are nourished by the energy created by people having fun. Entrusted with the hopes and dreams of this far-off enchanted land, Seiya must now use his many skills to bring Amagi back on its feet, or watch it crumble before his eyes.

Kikuko Misuji, more often called "Nikuko-chan," is known by everyone in her small northern town as the happy fat lady at the grill. Having lived arduously traveling from man to man and town to town for the bulk of her life, Nikuko-chan finally seems to have settled down on a houseboat docked in the bay with her daughter—also named Kikuko. Together, the pair does their best to find their place in the world. For the bold and brash Nikuko-chan, her spirited behavior easily guides her toward the earnest goal. However, for the quiet and reserved Kikuko, who is often embarrassed by her mother's antics, each day can be just as uninspiring as the last. From middle school drama to solving the mystery of her strange classmate Ninomiya, Kikuko's adolescence is full of many twists and turns.