Appearance
Asuna has long, orange-brownish chestnut hair and hazel eyes. In the early levels of SAO, she wore a dark red leather tunic with a lightweight copper breastplate and leather pants with boots up to the knees along with a hooded cape. After joining the «Knights of the Blood», she wore a red and white uniform that all KoB members wear and wielded a rapier made by Lisbeth, called the Lambent Light.

Asuna's B-W-H measurements were 82-60-83[9] in the web serialization, but this has been changed to 80-59-82,[10] for her SAO avatar.

Asuna's original avatar in ALfheim Online was the Fairy Queen, Titania. She wore a white outfit with a long white skirt, a crop top showing her belly, and a red ribbon that went around the topmost part of her top that came together to make a bow. She went barefoot, and wore a white strip around her
ankles.
Personality
Asuna originally did not care about dying in the game before meeting Kirito. That meeting drastically changed Asuna's personality and outlook on life. She soon takes most things Kirito says to heart and looks to him for help, using him as somewhat of a lifeline.

Asuna is a kind and helpful young woman who, similarly to Kirito, cannot abandon another in trouble. She takes the game very seriously and is determined to clear it before Kirito tells her to enjoy SAO a bit. Asuna is also somewhat proud and despite her kind personality, she will not hesitate to get physical with those that challenge her authority or make fun of her abilities, such as cooking. She even challenged Kirito to a duel after an argument over how to handle a Field Boss. She is not afraid to act out on her own and will take matters into her own hands from time to time.

Asuna, in a similar manner to Kirito, is someone who can be controlled and manipulated by her emotions. This is evident during Kirito's final duel with Heathcliff on the 75th Floor, when she resisted her paralysis, jumped in front of Kirito, and took an attack that would have otherwise killed him. She also cannot handle seeing others die in front of her, such as when she recklessly attacked The Gleam Eyes after seeing the Aincrad Liberation Force players getting slaughtered.

In ALO, after being saved by Kirito, Asuna's personality had not changed a bit except that she was not as proud as she was in SAO. Her personality began to develop further still after meeting Yuuki in the events of Mother's Rosario. Seeing how Yuuki still moves forward, despite knowing her death is inevitable, Asuna takes after her and resolves to keep moving forward, no matter what happens.
Relationships
Kirigaya Kazuto (Kirito)

Kirito is Asuna's partner and main love interest in the series. Among all the people Asuna has met, he is the closest and dearest to her. Originally the two of them only thought of clearing the game, but their relationship began when they partied on the 1st Floor. During the boss fight on the 1st Floor, Kirito called Asuna by her name for the first time, noticing earlier her character name below the HP gauge. Asuna was also one of the two people who knew the reason why Kirito called himself a Beater. As the series progresses, the two of them fall in love with each other. After the two of them declared their love for each other, they are only concerned for the other's safety.

This led to the two characters getting married in-game where they resided on the 22nd Floor for two weeks as their honeymoon until being called back to the front lines. During those two weeks, Asuna reveals to Kirito and Nishida that in the beginning, she would cry due to the fact she was trapped in a death game and she would take that sadness and turn it into determination thus allowing her to level up extremely quickly. She explained to them that it was Kirito who taught her that there were people who were trying to experience this world for what it is and that he was the reason why she was alive and looked forward to tomorrow.

Their relationship is very serious, to the point that they cannot live on if one of them dies. An example is shown when Kirito asks Asuna not to take part in the boss fight in the 75th Floor to which she replied that if he did not return, she would commit suicide, thus she refused not to take part in the boss battle and said that she would protect him. As Heathcliff was swinging his sword at Kirito after the boss fight, even though she was supposed to have been paralyzed, Asuna was able to jump in front of Kirito, taking the hit for him. Because of Asuna fueling Kirito's determination when Kirito was stabbed by Heathcliff, he was able to successfully defeat Heathcliff by stabbing him in the chest after a message appears announcing that Kirito was dead.

Asuna also seems to have put a lot of faith in Kirito. An example is when Sugou Nobuyuki trapped her in the World Tree in ALfheim Online (ALO) after her escape from SAO. Asuna asked Kirito to save her, and assured herself that he would come for her. After Kirito rescued Asuna in ALO, the two of them finally met face to face and they officially became a couple in the real world.

The two maintain a happy relationship even a year and a half after the SAO incident. Even though Kazuto had decided to go to school in America for the summer to pursue his mechatronics career, he asked Asuna to accompany him overseas, as he could not live without her, even if it was a very selfish desire. Asuna replied that her answer to that question was decided a long time ago.

When Kazuto was kidnapped after being admitted to a hospital due to being injected with a dangerous drug, Asuna never gave up on finding him and was eventually able to pinpoint his location.

Epithet:Flash
Berserk Healer

Age:15 (Beginning of Aincrad Arc)
17 (End of Aincrad Arc, Fairy Dance Arc)
18 (Phantom Bullet Arc, Alicization Arc)

Birthdate:September 30, 2007

Gender:Female

Height:168 cm

Weight: 55 kg

Family:Yuuki Shouzou (Father)
Yuuki Kyouko (Mother)
Yuuki Kouichirou (Brother)
Kirigaya Kazuto (Boyfriend/In-Game Husband)
Yui (In-Game Daughter)

Occupation:High School Student