Like her master, 20 is very underhanded and resorts to any methods in order to win, even hurting innocent children like Honoka. It is also revealed that she has romantic feelings for Loki, despite his occasional mistreatment of her. However, Loki does care for her and was willing to risk his life to save her from Yami.
20 is a young woman with short unkempt brown hair and a fairly endowed figure. She is typically seen in a yellow A-shirt and suspenders and has a type of goggles on with night vision seekers on it and has a P90-like automatic airgun with her. She also seems to have some type of markings on her body that are green that seem to be camo make-up
20 first appears during Loki and Siegfried's abduction of Haruo Niijima in order to break up the Shinpaku Alliance. Nijima, who overhears their plot, grabs 20's breasts to escape but is still captured by Siegfried. She later fights Miu Fūrinji on a truck driven by Number 43 and gains the advantage with her gun and prong. However, Miu got up due to her training and gave her a well desirved punch in the stomach, defeating her. She later takes Kenichi Shirahama's sister Honoka hostage and threatens to kill her if Kenichi attempts to fight back against Loki. This continued until Natsu Tanimoto, a.k.a. Hermit, knocks her out and rescues Honoka, allowing Kenichi to defeat Loki.
In the final battle with the Shinpaku and Ragnarok, she aids Loki and his new eight fists in his attempted coup d'état, but they are defeated by Berserker, after which they disappear for the remainder of the battle.
Following Loki's invitation to join Shinpaku by Niijima to be used as a spy with Number 20, Loki is seen sending information about YOMI to Niijima, who he appears to be working with to gather information despite Number 20's objections due to her dislike of Niijima
Loki and Number 20 travel on board Diego's cruise ship and watch him and Caster fight the beginning roundsand are amazed by their strength and Loki even comments how he'd be no match for her. They both later hide from the guards after hearing about the bomb on board but still get caught and escape the ship.
Hearing about YOMI's death match, Loki and Number 20 go watch it and are shocked to see Hermit is the challenger against Chou Enshin and Loki comments how strong Hermit is since before and actuallycheers for him. After Hermit wins, they are caught again and Loki leaves Number 20 behind. However, he did so to gather his men and come save her worried over her condition.