Ryomen Sukuna

Over a thousand years ago, an infant Ryomen Sukuna resided in the womb of his starving mother alongside his twin, Sukuna not wanting to starve himself consumed his twin. As a human sorcerer, Sukuna had killed many of the sorcerers from the golden age of jujutsu. Around this time Sukuna met Uraume and accepted them as his subordinate due to their exceptional cooking. During the Heian period, Sukuna was invited to the Harvest Festival in the capital and worshipped as an idol after annihilating the Northern Fujiwara Clan's Five Empty Generals and Sun, Moon, and Stars Squad. During the festival, Yorozu embraced him thinking he was lonely, only to be driven away by Uraume. Yorozu then expressed her wish to alleviate his loneliness, only to be slashed by him in disgust. Sukuna and Yorozu one thousand years ago. Before his death, Sukuna was helped by Kenjaku to live on after death by splitting his soul into twenty cursed objects created from his fingers. Despite binding vows being used to preserve their existence in exchange for not doing damage, Sukuna's fingers continued to grow stronger over the millennium, eventually being designated as special grade cursed objects by Jujutsu High.

Viper

Valentino "Viper" Valdez is the infamous leader of the violent gang Las Serpientes. Captured and incarcerated five years ago, Viper has taken control of the Mesa Verde Correctional Facility in New Mexico. The prison is plagued by severe issues, including overcrowding and corruption.