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 RECT Progress.
Asuna is voiced by Haruka Tomatsu in Japanese, and Cherami Leigh in English.