Patty Crew is a member of the esper organization P.A.N.D.R.A. She was previously part of the criminal group Black Phantom, where she served as a mind-controlled assassin. During a mission involving Kaoru Akashi and others, she became a rescue target. Kaoru destroyed the organization's control over her, triggering a mind-control self-destruct program that caused Patty to attempt suicide. The presence of this program may have contributed to the incomplete success of her subsequent Pandra Boost procedure. She ultimately survived and joined P.A.N.D.R.A.

Her esper ability synthesizes psychic powers to transform her body into mist, granting significant versatility in combat and evasion. This power is consistently noted as a defining trait.

Patty exhibits a notably reserved personality but displays intense enthusiasm for yaoi pairings involving male members of P.A.N.D.R.A. or adversaries like B.A.B.E.L. agents. This fujoshi tendency manifests in creating doujinshi, designing costumes, crafting character-themed bento lunches, frequenting otaku-centric locations such as Akihabara, and scripting school plays based on her interpretations. She has used her psychic abilities to observe male colleagues hoping to witness suggestive interactions. The origin of these traits is unclear, though they may relate to side effects from her deprogramming, as other freed Black Phantom members developed similar otaku inclinations.

Attending Shogakukan 6th Private Academy, Patty shares classes with Shiho Sannomiya from B.A.B.E.L., resulting in a persistent rivalry. Despite this tension, they maintain functional interactions during school activities. No verified information exists about her life prior to Black Phantom's control.