Ren Amamiya,, also better known as Joker, is the main protagonist of Persona 5, a 2016 role-playing video game by Atlus. He is a second-year high school student who is expelled due to being falsely accused of assault by a corrupt politician. As a result, he leaves his hometown and moves in with a family friend in Tokyo to serve a one-year probation. Upon transferring to a new school, he and a group of other students awaken to a supernatural power known as the Persona.

Soon after discovering these powers, they form a vigilante group known as the Phantom Thieves of Hearts with Joker as its leader, as they explore around the Metaverse, a realm consisting of the physical manifestations of humanity's subconscious desires, and remove malevolent intent from people to cause a change of heart within them so they can answer for their crimes.

Joker also appears in several of the series' spin-off media, as well as in cameo appearances outside of it, such as being a playable character in the crossover fighting game Super Smash Bros. Ultimate. He was designed by Persona series artist Shigenori Soejima, and is voiced in Japanese by Jun Fukuyama and in English by Xander Mobus. He has also been portrayed by actor Hiroki Ino in the game's stage adaptation. Despite his canon name, Joker's given name can be customized in the game.