Piano no Mori ~The Perfect World of Kai~ is a Seinen Manga by Makoto Isshi, currently running at 22 volumes.
It was adapted by Madhouse in 2007 as an animated film, covering a majority of the childhood arc up until the end of the concours.
A new anime adaptation, in the form of a series, is being produced by Fukushima Gainax for the Spring 2018 season and will run for 12 episodes. It's been licenced by Netflix for worldwide release in Fall 2018.
This series provides examples of:
- Blinding Bangs: Shiba, during the childhood arc.
- Bowdlerize: The exact natures of Rei's profession and the Edge of the Forest itself are obscured in the animated film adaptation. Savvy enough viewers may infer from life experience and figure it out immediately. More innocent viewers, however, can easily mistake the Edge of the Forest as merely the town's slums and Rei's job as that of some sort of bar hostess, as opposed to what they are explicitly stated to be in the original work (i.e. the town's Red Light District and a prostitute, respectively)
- Dude Looks Like a Lady: Kai has taken much of his looks from his mother. So much so that the dorm manager mistook Kai for a girl, no realizing until she gave him a dress and Ajino had to point it out for her.
- Fat Bastard: Kinpira.
- Generation Xerox: Shuhei acts as the Unknown Rival to Kai, much like how his father developed the same dynamic toward Ajino, who also mentors Kai.
- Jerkass: Daigaku Kanehira, otherwise known as Kinpira, is a child who constantly bullies Shuhei and Kei throughout the childhood arc.
- Market-Based Title: The anime film is sometimes known as The Piano Forest.
- Meaningful Name: Kai full name written in Eastern order, Ichinose Kai, is a pun for "ichi no sekai," which roughly translates to "#1 of the world."
- Performance Anxiety: Aside from some of the background characters, Takako suffers through this before her performance in the South Central district preliminaries for Japan's national piano competition, which had been exacerbated by Shuhei's presence. Kai helps her through it.
- Pragmatic Adaptation: The animated film takes steps to ensure that it works as a self-contained story by taking out elements that lead into the story past the Time Skip.
- Red Light District: Kai lives here. It's nicknamed "The Edge of the Forest" for its location in the city and is known for being a Yakuza lair.
- Satellite Love Interest: It's as if Sae exists almost exclusively for Kai to have someone to relate to and to be his girlfriend, since she doesn't have any plot relevance past the chapters that lead to them hooking up.
- Single Mom Stripper: ...Well, prostitute, anyway. Reiko.
- Son of a Whore: Kai's mother, Reiko, is a prostitute of his town's Red Light District.
- Sweet on Polly Oliver: Saga toward Maria, Kai's cross-dressing disguise for the P-Club.
- Technician vs. Performer: One of the central themes of this work. In this case, both schools of thought are exemplified through the two leads. Shuhei is the Technician and Kai is the Performer.
- Time Skip: One spanning several years occurs after Shuhei moves away and the piano of the forest is destroyed by lightning and a forest fire.
- Unknown Rival: Shuhei has a massive inferiority complex and considers Kai his greatest rival, despite how the music world has initially judged their respective skills. Kai, on the other hand, only sees Shuhei as his best friend and is perplexed whenever the former treats him like an opponent.