|Non Canon: Some or all events and details given in this article, may be considered non-canon to the main story.|
Strea (ストレア, Strea?) is one of the characters in Sword Art Online: Infinity Moment, Sword Art Online: Hollow Fragment, and Sword Art Online: Lost Song. She is voiced by Misawa Sachika, who also voices Kuroyukihime in Accel World, a series by the same author. In Lost Song, Strea will be a Gnome. 
Infinity Moment/Hollow Fragment AvatarEdit
Strea's Infinity Moment and Hollow Fragment avatar has lavender hair which goes down to the base of her neck with two long strands on either side of her head which go down to the top of her breasts. She has two moles on her left breast inside her cleavage. Her eyes are red-violet, nearly pink.
Strea wears a lilac-color, strapless dress with a black piece of fabric going across the breasts and down to her stomach, below an intricate coat. This coat is made up of violet and plum shaded components, reaching as far down as the hem of her dress but also leaving some areas open which expose the dress below. Above that she wears a collar of the same violet of her coat, outlined in lavender with a red jewel securing the collar in place. It appears that the components that go over her detached black sleeves are connected to this collar. These components that go over the black sleeves appear to cover them completely except for at the wrist and hand where it joins to her finger. She wears plum stockings, which have, much like the rest of her outfit, whorls etched on. They go up under the dress and are connected by something triangular.
Strea's main weapon of choice is a large, purple two-handed blade with silver edges.
Lost Song AvatarEdit
Strea's ALO avatar has brown hair, red eyes, and an outfit that resembles her SAO outfit..
Strea started tailing Kirito after the events of the 75th Floor's boss fight. She did so without him noticing, even with his high-level detection skill. Although his skill could not detect anything, he could feel her presence and, eventually, forced her to reveal herself. Strea greeted him with a smile and introduced herself, though she did not tell Kirito the reason why she had been tailing him in the first place.
Throughout the story, Strea would be seen in the Labyrinth searching for «something». She would claim that this «something» was important, but she had no idea what it was or what it looked like. She would also occasionally experience headaches, which would become stronger the further the Clearers advanced in reaching the top floor. After getting close to the 100th Floor, Strea joined the Clearing group in subduing the Floor Boss and had a severe headache, before suddenly changing her personality and disappearing into thin air.
Strea reappeared on the following floors, attempting to prevent Kirito and the others from completing the game. She reappeared after Alberich attempted to eliminate all the players (except for Asuna) from the game by using a special blade that held an incurable poison, which would slowly kill anyone who was injured by it. Protecting Kirito from getting hit, Strea slowly succumbed to the blade's poison until she surprisingly fused with the «Hollow Avatar» and disappeared.
Strea was later revealed to actually be a mental-health program, similar to Yui, who was somehow able to appear using an unused avatar that was still registered in Aincrad. However, the near-death experience had slowly altered her data and resulted in her fusion with the «Hollow Avatar». Vowing to rescue her, Kirito and the group agreed to save Strea by reaching the 100th Floor.
After defeating the Hollow Avatar and the other mental-health programs, Strea appeared in a large monstrous form and attempt to eliminate the Clearing group. Her defeat lead to the Aincrad being cleared and her temporary freedom. Strea slowly disappeared as her fusion with the Hollow Avatar had revealed her true identity as a mental-health care program in the game, and led to her returning to her true form. At the last minute, Yui absorbed Strea's program and assured the rest of the group that she was still alive.
Heathcliff (Kayaba Akihiko) reappeared shortly afterwards to congratulate the group for making it all the way to the end, and explained that the cause of the glitch which resulted in his disappearance was partly due to Strea accumulating all the negative emotions from the players, which accidentally "overloaded" the game for a brief period of time.
- See: Strea/Image Gallery
- Strea considers Yui to be her older sister.
- Strea has a Navigation Pixie form in Lost Song.
- ↑ 1.0 1.1 Dengeki PlayStation vol. 580, via http://gematsu.com/2014/12/strea-argo-join-sword-art-online-lost-song