Kirigaya Suguha

is the cousin of Kazuto, she was raised along with him as his sister. She is an accomplished kendo practitioner following in her grandfather's wishes. She later takes up VRMMORPG playing in «ALfheim Online», as Lyfa (リーファ) a Sylph warrior.

Background
Suguha originally disliked VRMMO's for the reason it hid people's nature and reality. She took up ALO in order to understand Kazuto better when he was trapped in SAO. She won the Sylph tournament earning the title as strongest Sylph before Volume 3. She learned how to play ALO from her classmate, Recon.

Fairy Dance
She first is overjoyed to find Kazuto returning home, and tries to be respectful of his temporary weakness. She is also saddened by her brother's new found attachment to Asuna. After a couple months after Kirito's return Kirito challenges Suguha to a kendo duel, though she wins she is surprised at Kirito's unorthodox skills. Yet she is also happy that Kirito once again shows interest in kendo.

Caliber SS
She comes to Kirito to inform him that Excaliber's location has been found.