Yuki is an artifically-created human with light skin and long, dark-brown hair. She wears a light-gray, skin-tight jumpsuit, along with a blue and white jacket. Her arms, legs, and the ends of her hair are coated in ice.
In KillGames 2, her appearence stays mostly the same. Her hair is a bit shorter, and is fashioned to look similar to a bow (frozen ice keeping her hair in place). Her jacket is smaller and puffier, and her jumpsuit is now black.
In KillGames: Rechained, her design was changed to accompany her new story of her being part-demon. She wears a gray jumpsuit similar to her original design, though trades the jacket for a dark blue coat and a scarf. She possesses small horns that grow when she goes into Yuki-Onna form, and she has two crystals imbedded into her body, on one her chest and the other on her forehead. Bright blue streaks are seen throughout her body.
Yuki is a synthetically-creating human made by an unknown organization, that wished to create a "next step of human evolution". Born with the mysterious powers to manipulate ice, a freak accident because of these ice powers caused her to destroy the lab she was held in, destroying it and killing everyone in it. Found in the wreckage by Adam, he was impressed at the damage she could cause, and trained her to become the ultimate fighter. Forced to join the tournament against her will, she wishes to make it out of the tournament alive.
In KillGames, Yuki appears as a secondary protagonist in Redge's story. Redge and Lane both meet her in Chapter 1, witnessing her kill an Anarchist. Scared out of her mind of them, she tosses a ball of ice at Lane, prompting Redge to begin a fight with her. Yuki ends up defeated, but Lane, realizing she's scared, stops Redge. Wishing to help her get out of the KillGames, Lane decides to let Yuki join them, despite Redge's doubts.
In Chapter 3, Yuki reveals more about her past to Redge, talking about her past and Adam. After the fight against Misery and Colt, they are almost about to be crushed by debris before she stops them by pushing them away with an ice wall. However, she gets kidnapped by Zmei.
In Chapter 4, she fights against Zmei in the Neon Tower. After she defeats him, she saves him from falling off the tower, and becomes friends with him. Finding her, Redge attacks Zmei, but Yuki protects her new friend and Zmei eventually joins them.
In Chapter 5, she, Redge, Lane and Zmei are transported into a hellish pocket dimension by Soul. After Redge is injured, she and Lane protect him from legions of demons. After Zmei is injured, she gains the courage to face off against Soul, defeating her. She manages to escape, but is able to listen to the last words of her friend before falls into the abyss. Wishing to avenge his death, she gains the courage to fight alongside Redge and Lane in the final battle.
In the Final Story, after either Redge or Storm win the KillGames, she goes to her injured father. Despite Adam's wish to be left alone, especially for what he did to Yuki, she decides to forgive him despite his actions, and the two get on good terms. However, when Soul attempts to kill her, Adam decides to sacrifice his life to protect her. Saddened by her father's death, she fights alongside her friends against Mutant Soul. When she overpowers the heroes, Mutant Soul grabs Yuki, and attempts to eat her, but in the nick of time, Redge in Full Demon Form flies at Soul and decapitates her. Soul drops Yuki, but she is grabbed by ARMA right before she hits the ground.
After Soul and Maligna are killed, Yuki is seen alongside the surviving eight, outside the arena and watching the sun rise. It is implied that after the game's story, she was adopted by Redge and Lane.
Yuki, despite being trained to kill, absolutely hates violence. She will only use her powers on another person if she is either forced to or threatened, and even then she goes on the verge of tears when she kills someone. She is shy and distant, mostly because she fears her ice powers and has had little interaction with anyone who doesn't want to kill her. When she warms up to other people, specifically Redge and Lane in the Story Mode, she becomes more cheerful and friendly, and learns how to use her ice powers to help people.
In KillGames: Rechained, her personality was changed. She is portrayed as a bit more mature and less cheery than her original counterpart, closing her emotions from others due to her trauma and belief that she only exists to kill others. As time goes on, she warms up to others.
Yuki was born with the ability to manipulate snow and ice. In combat, she often uses it to form icy weapons, creating icy blasts to freeze enemies, and skate on the ice she leaves behind when she walks to increase her mobility.
Yuki appears as a playable character in KillGames.
Yuki appears in Fantendo Smash Bros. Combat as a Summoner Orb character. She also appears as a spirit.
Fantendo Smash Bros. Battleground
Yuki appears as a playable character.
Yuki appears in Fantendo's Card Cataclysm as a Hero Card (and as of right now) being the only character from KillGames represented in the game.
- Yuki's original design is similar to Kula Diamond from the King of Fighters series. The creators eventually felt this design was a bit too similar to her, and so, when Rechained was concieved, she was redesigned. Her design takes inspiration from characters like Vatista from Under-Night in Birth and Ramlethal Valentine from Guilty Gear.
- As a result of this, she resembles Euthany from KillGames 2, who had similar inspirations.