Asuna Yuuki, or just Asuna for her avatar name, is the main deuteragonist of the popular light novel/manga/anime series, Sword Art Online. She is Kirito's girlfriend, fiancé, and in-game wife. She is an incredibly fast rapier user (earning her the nickname "Lightning-Flash") and was the second-in-command of the top guild in SAO, the Knights of the Blood Oath. She is also the daughter of Shouzou Yuuki, the former CEO of a game company called RECT Progress.
Asuna is voiced by Haruka Tomatsu in Japanese, and Cherami Leigh in English.