With the start of the Chopin piano competition, Kai Ichinose, Shuuhei Amamiya, and many other hopeful musicians from around the world strive to reach the top. The stakes have never been higher, and the judges are rigorous when it comes to selecting the winner out of the plethora of talented pianists. This competition is so harsh that even famous prodigies can be easily eliminated. Some play for the money, some play to fulfill their duty to their families, and yet others play for their music to be heard. However, the only one who can reach the top is the one who embodies the spirit of the music Frédéric Chopin crafted for future generations. With the stakes higher than ever before, rivalries, friendships, and family ties will be tested, and each pianist will find their own sound. [Written by MAL Rewrite]

Koyama Yuzu is running an antique shop. Mayu, a cat god (nekogami), is living off Yuzu and leads an idle life playing games. Lots of other gods visit Mayu and enjoy merrymaking.

Piano no Mori tells the story of Shuuhei Amamiya, a transfer student, and Kai Ichinose, a problem child from the rough areas of town. Upon transferring to Moriwaki Elementary and telling the other kids about his talent for piano, Shuuhei quickly finds himself as the victim of bully Daigaku Kanehira. 

Daigaku dares Shuuhei to find and play a cursed piano in the forest, which leads him to meet Kai, who claims to be the owner of the piano and the only one who can play it. Intrigued, Shuuhei follows Kai to the hidden piano in the forest and listens to him play a beautiful medley.

Earning the respect of not only Shuuhei but school music teacher Sousuke Ajino as well, Kai now finds himself formally learning how to play the piano.

[Written by MAL Rewrite]

Two years after saving the world from a cataclysmic event, the members of the activist organization Avalanche have gone their separate ways. Tifa Lockhart opens a new bar, and her childhood friend Cloud Strife starts up a motorcycle-based courier service. Although most of their former allies have fallen out of touch, Cloud and Tifa live in fragile peace with their two young wards Marlene and Denzel. Their life together begins to crumble as a contagious plague and overwhelming grief pull Cloud away from his newfound family. While distancing himself through his work, Cloud is attacked by three silver-haired figures in black uniforms who bear a passing resemblance to his bitter rival, Sephiroth. As the antagonistic trio stalks Cloud and brings harm to his loved ones, the former mercenary struggles against his own demons while fighting to protect his family and prevent the will of Sephiroth from returning to the planet.