"A masked figure rumored to grant one's dreams. Why he does this, and who he is, is a complete mystery."
—Persona 2: Innocent Sin introduction
It is rumored that the Joker can answer wishes submitted to him by a phone call. However, if the person who summons them doesn't have a wish on their hearts, Joker instead claims the dreams of his victims, and reduces them to shadows of their former selves. The Joker tends to leave behind flowers as a reminder to his victims of the sins they've committed.
It is later revealed that the Joker is in actuality Jun Kurosu, a form he took to claim punishment from those he deemed guilty for the fire that nearly killed Maya Amano years ago. He was also guided into this role by Nyarlathotep, who took the form of his father and manipulated Jun into doing his bidding.
After Joker is defeated at the Caracol, he is possessed by Nyarlathotep and is forcibly transformed into Angel Joker.
An A-Rank BattleNet opponent who can supposedly grant any wish. He has a collection of rare demons, and is said to act unpredictable and have a lot of style. He gives a Scylla after 7 defeats, Clotho at 17 defeats, and Lachesis at 27.