She is Tomo, Misao, and Kanade's senpai. She was also involved in the plane crash 3 years ago, and nearly died. Her limbs have been replaced by machinery after the accident, thus making her able to store weapons in her arms an legs. After her sister gave her soul to the Asura Machina, she've been trying to find a way to save her. Due to her calling her sister in the Asura Machina Shuri, and telling You Susugihara that she was acting as Shuri and is really her twin sister Yukari, we can assume that Shuri has been acting and was always Yukari.