Strictly speaking this outfit is not something that should be worn to an actual battle. But thankfully, this is an VRMMORPG based anime and much like every other online game armor logic, the less clothing they have on, the higher the defenses and character level is.
This cosplay is of Asada Shino, a character from the second season of Sword Art Online which is set in the virtual reality game world called Gun Gale Online. Despite the change in the VR worlds, however, the creators decided to stick with the first installment’s title which is the game which started the main character adventures. Despite the fact that some have continued to express their valid discontent with this anime it still being popularly accoladed with plenty of followers all over the world. One such follower is cosplayer, Nayupeta, who has brought to life the top in-game sniper, Asada Shino (a.k.a. Sinon) through her cosplay tribute.
Photo credits: けーたろ