Following the plot of the game, it switches between the viewpoint of different characters as they face off against each other in the tournament. Commonly following the story from the viewpoint of Yu Narukami, Aigis, Yosuke Hanamura, Mitsuru Kirijo, and Naoto Shirogane as they face off against the other characters. Both Yosuke and Aigis face off against Shadow Labrys.

A teenager who was orphaned as a young boy returns to the city of his childhood. Shortly after transferring to Gekkoukan High School, he is attacked by Shadows &mdash; creatures that feed on the minds of their victims. The assault awakens his Persona, Orpheus, his only chance at defeating these creatures of the night. He soon discovers that he shares this special ability with other students at his new school. From them he learns of the "Dark Hour," a hidden time that exists between one day and the next, swarming with Shadows. He joins the Specialized Extracurricular Execution Squad (SEES), and with his new friends, confronts the threat of the Shadows. 
After signing a contract in which he "accepts his fate of his own free will," the main character battles with the other members of SEES against the Greater Shadows, incarnations with traits and appearances similar to those of the first 12 Major Arcana of the Tarot. While this is occurring, he continues to encounter and eventually befriends the child who gave him the contract to sign at the very beginning of the game, an entity who refers to himself as Pharos, and is really the incarnation of Death, the 13th Arcana.

Following a string of mysterious murders, transfer student Souji Seta and his new friends have followed the legend of the Midnight Channel and found themselves pulled into another dimension! In this twisted TV world, a person’s innermost secrets materialize as a Shadow — an entity that may become a powerful ally, or something much worse...
 
Based on the popular Persona 4 video game!
 Source: UDON Entertainment

The story is a continuation of the events depicted in the game Persona 4 Arena and begins the day after it concludes. The Midnight Channel is back on the air and once again broadcasts a strange advertisement for another fighting tournament christened P-1 Climax, that shows members of the Investigation Team and the Shadow Operatives in combat. Just moments after this, Inaba is subject to a power outage and is engulfed by a bizarre red fog.
 
(Source: Megami Tensei Wikia)

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