Nina Williams is a character from the Tekken game series. She is a cold-blooded assassin who made her first appearance in the original Tekken and has appeared in every Tekken since. She is one of only four Tekken characters to appear in each game and the only female character to have appeared in every installment. She has a notable love/hate relationship with her younger sister, Anna Williams. Nina was born and raised in Ireland, as was her sister, Anna Williams. From a young age, both were taught various forms of martial arts. A sibling rivalry boiled between the two. Both girls adored their father, Richard Williams, and they often battled for his attention. Nina was trained in assassination martial arts and borrows concepts from Aikido and bone martial arts, which was ideal for her job, as she quickly became a world-renowned assassin. Nina then entered the King of Iron Fist Tournament when she was hired to assassinate Heihachi Mishima. (biography provided by: tekken.wikia.com)