He was designed by Persona series artist Shigenori Soejima, and is voiced in Japanese by Jun Fukuyama and in English by Xander Mobus.

In the game, he is a second-year high school student who is charged with assault by Masayoshi Shido, an influential politician in the Cabinet of Japan, after witnessing him harassing a female subordinate.

At the court hearing, Joker is told he must serve a one-year probation and transfers to Shujin Academy, a school in Tokyo which will accept him with his current criminal record.

They explore the Metaverse, a supernatural realm consisting of the physical manifestations of humanity's subconscious desires, to change malevolent intent in the hearts of adults.

Despite primarily being a silent protagonist, Joker occasionally speaks short phrases during cutscenes and battles; being voiced in Japanese by Jun Fukuyama and in English by Xander Mobus.

[8] Amamiya was chosen by the anime's producer who thought that the combination of his full name, which means lotus rain palace in Japanese,[d] sounded "quite poetic" together.

[18][19] In the Metaverse, his apparel changes to a stylized black trenchcoat with a masquerade mask and winklepicker shoes, which were described as being designed after Belle Époque fashion.

[11] As the main theme and narrative of Persona 5 revolves around crime and vigilantes triggered by Joker voluntarily choosing that path, Soejima needed to convey this while allowing the character to suit whatever dialogue choices the player decided upon.

As the "phantom thief" premise was a common stereotype in fiction, Soejima initially drew Joker and the rest of the game's main cast in a style similar to shōnen manga, but these designs were scrapped as they clashed with the series' realistic aesthetics.

Despite Joker's uniformed appearance being meant to give off the impression of someone who is kindhearted and loyal to the system, his true nature is free-spirited and rebellious, with him being the type of person who plans things without telling anyone.

[40][41] His appearance in Ultimate was met with praise, with game journalists noting the level of detail and how faithful his transition from Persona 5 was, as well as how enjoyable he was to play as.