Figured out a couple face claims/possibilities for Hatter's HSR AU variant, for her more human identity as Tara (brought to you via mask) its Aki from Yu-Gi-Oh 5ds & she's a popular mangaka whose characters come to life as a result, including Cheshire & Red. For her Madelyn Shire identity I'm considering a kitsune lady that I don't remember the name of atm unfortunately TT
But basically the rough backstory of Hatter in HSR is that she was born to an IPC father and a foxian mother who was a member of the Sanctus Medicus. Madelyn would go on to eventually be invited and join the Genius Society for her works revolving around memory studies, namely bejnv able to recover memories that were erased by Cremators. As a result of testing one of her projects on herself she remembers something from her childhood that results in her going "mad" and brutally experimenting on and eventually killing her parents and several of her father's IPC buddies and her mother's sect of the Sanctus Medicus, documenting each experiment with the sort of medical thoroughness she was known for before disappearing. These tapes were confiscated by the IPC for their disturbing nature but would eventually lead to some medical breakthroughs, none of which would be attributed to Madelyn.
Years later a Masked Fool known as Hatter would appear, targeting IPC officials that she would reveal to be corrupt with her heists. She would be traced to one of the works made by Tara Hightopp, a mysterious yet popular mangaka from Planarcadia. Hatter showed up alongside her siblings Cheshire (Galaxy Ranger) & Red (Doctor of Chaos), and together they worked to eliminate the corrupt and evil lurking behind the scenes on a galaxy-wide stage, but since the three would be thought to be imaginae there was very little the IPC could actually do to stop them.
