Naru

Season 5 (Written during)
Yu Narukami is a major character and participant in Grace's killing games, most recently, Season 5. He is considered to be the protagonist of this story, and is apart of team Gale. Despite the fact that he is on that team, he has somehow gained membership into the faction of "Chad" within team Mist.

Yu Narukami is a raging bisexual and has relations with both Naoya and Mitsuru.

He has a little sister, Nanako, who, despite her age and looks, will clock Yu Narukami into next week of he doesn't make her food or give her hugs.

He is most famously involved with the revival of Mitsuru Kirijo.

He assumed Mitsuru was just an apparition, until the famous words of his partner reassured him that she was alive by saying "Fuck yeah man, I see her too!"

Season 5 (Written After)
The above information, after having completed Season 5, has now been proven completely fucking wrong, holy fuck.

Shadow Yu Narukami, henceforth dubbed "Naru", is a major character in Season Five. In Chapter One, Naru "Awakens" alongside the rest of Team Gale's participants, feigning ignorance and shock towards their current situation. He takes the natural role of leader, and is commonly found alongside Nanako in Gale's side, and doing miscellaneous tasks in Mist's side, examples of which being cooking with Chie, and racing down the halls.

In Chapter Two, Naru's true nature was revealed in a private conversation with Ren, where he appeared apathetic and tired of the antics both Mist and Gale had pulled. He also appears to be a bit sadistic, as he took pleasure in later breaking Ren's finger, which the latter then blamed upon himself punching a wall.