She is an Arrancar and the leader of the Giant Hollow Fortress which attacked Karakura Town. She wears a modified version of the standard white Arrancar uniform resembling a dress. She has pink eyes, long purple, curled hair and wears purple lipstick. Her mask remnants resemble the head of a rabbit complete with ears. When the Karakura-Raizer team defeat some Hollows, she appears along with a giant fortress floating in the sky. She claims that Sōsuke Aizen has given her "great power." After Ururu Tsumugiya defeats all of the Hollows coming from the fortress, Kon, Tatsuki Arisawa, Keigo Asano, and Chizuru Honshō arrive at the fortress. While Tatsuki is not looking, the Unnamed Arrancar attempts to impale her throat. Tatsuki grabs the Arrancar's Zanpakutō and the Arrancar is impressed that Tatsuki was able to dodge her attack.