Haruka Tomatsu (Japanese), Cherami Leigh (English)
Asuna is a friend of Kirito, and a sub-leader of the Knights of the Blood Oath, a medium-sized guild acknowledged as the strongest guild in Aincrad. Being one of the few girls that play SAO and extremely attractive, she receives many invitations and proposals. Asuna is a strong-willed, accomplished player known in-game as the "Flash" (閃光, Senkō?
) for her extraordinary sword skill.
Later, she falls in love with Kirito and they marry in-game. Towards the end of the SAO arc, she saves Kirito from a killing blow by Heathcliff at the cost of her life. However, her death was only in-game and she is shortly reunited with Kirito shortly after his death defeating Heathcliff.
Despite the completion of SAO, Asuna does not wake up and is instead detained in another VRMMORPG called Alfheim Online. She is forced to play the role of Titania the Queen of Fairies, with Nobuyuki Sugō, the man responsible for imprisoning her, playing as Oberon the Fairy King. This is done so that Sugō could marry Asuna in the real world, while she was unconscious, and thus take over RCT Progress Inc. She attempts to get out of the World Tree where she is imprisoned and escape going so far as to steal a GM card which she throws out of the window when she hears Yui's voice. Upon being freed she created two avatars for Alfleim, Asuna (being the healer of the team) and Erika (a battle type avatar) and went on living with Kirito.
In the real world, Asuna lives a very stressful life, and is constantly pressured to fulfill her parents' high expectations. Before the SAO incident, she led her life unquestioningly according to her parents' demands. However, after living in SAO and meeting Kirito, she gains perspective and looks back on her past with disgust. She eventually becomes Kirito's girlfriend, and dreams of marrying him and having a family with him in the real world when they saw a family at the park.