Noriko is a villain in the Usagi Yojimbo comics. She is Tomoe Ame's cousin but it is later revealed to be her half sister. She was hired by Lord Sanada to mine for gold and she enslaved numerous peasants to accomplish her goals, abusing them every step of the way.
She ran a secret gold mine with slave labor and worked the slaves to death. If any slave slowed down, she would behead a slave to threaten the others. She enslaved Tomoe and Usagi in her plot, but they later escaped with the slaves to foil her plans. Later she tried to blow up the mine with the slaves inside it when all the resources were gone.
Unlike the other villains, she enjoys humiliating defeated opponents and she killed her father. She is incredibly sadistic and isn't satisfied with simpy defeating her opponents. For example, in the flashback to her sparring matches with Tomoe, after she knocked the wooden sword out of Tomoe's hands, Tomoe declared Noriko the winner. Unsatisfied with simply winning the battle Noriko proceedes to continue beating her up, telling her that she'll decide when the match ends. She refuses to let her opponents die quick and honorable deaths and instead prefers make their deaths very brutal. When one of her henchmen asked if she intends to let Usagi and Tomoe die in the explosion along with the slaves, she said she instead intends a "special" death for Tomoe.
She also thinks like a petulant child. Whenever something doesn't go her way, she tends to go into an explosive rage, usually at the cost of the life of someone around her. For instance, when her biological father, who is also Tomoe's father, rejected Noriko as a daughter, she snapped and murdered him. And when Tomoe refused to pick up a basket for labor in the mines, Noriko killed a nearby peasant and threatened to kill more and more of them until Tomoe gives in and submits to her will. And she became absolutely furious when Tomoe and Usagi started a slave rebellion. She's also very impatient as she is quick to kill an exhausted peasant just to get the others to keep working. He also called out to Tomoe threatening to cut off parts of Usagi's body if she didn't surrender herself to her quickly enough, and when Tomoe did finally arrive, attempted to cut off Usagi's fingers to punish Tomoe for taking too long. She also hates failure as whenever a slave fails a task or gets too tired, she'll kill him or her without hesitation or remourse.
She also has a seething grudge against her sister Tomoe, due to how jealous she was of how Tomoe was loved and cared for by her parents as opposed to how Noriko was scorned and shunned not only by Tomoe's parents, but her own as well. In addition to beating her up during their sparring matches even after winning a match, Noriko glefully enslaved both her and Usagi and forced them to work in the mines. When she demanded Tomoe to pick up a basket for the mining, and Tomoe refused, even stating she'd rather die than do Noriko's, and by extension, Lord Sanada's bidding, Noriko decided to put the lives of innocent civilians on the line instead, killing one and threatening to kill more of them if Tomoe doesn't obey her orders, and blamed her for the death of the peasant she killed. When she told Tomoe that she was in fact Tomoe's illegitimate sister and that she had murdered their father Tatsutaro, she blamed Tomoe for his death as well, while beating her up. She insults and belittles her frequently, and, assuming she actually survived the cave-in, vows to kill her afters escaping the collapsing mine.