I'm a librarian who loves anime, manga, and reading a wide variety of genres.
"Julie d'Aubigny (1673 – 1707), better known as Mademoiselle Maupin or La Maupin, was a 17th-century swordswoman and opera singer."
One event from her youth, according to Wikipedia:
"Eventually, she grew bored of Sérannes and became involved with a young woman. When the girl's parents put her away in the Visitandines convent in Avignon, Maupin followed, entering the convent as a postulant. In order to run away with her new love, she stole the body of a dead nun, placed it in the bed of her lover, and set the room on fire to cover their escape. Their affair lasted for three months before the young lady returned to her family. Maupin was charged in absentia—as a male—with kidnapping, body snatching, arson, and failing to appear before the tribunal. The sentence was death by fire."
Wow. If I read that in a fiction book, I would say it's over-the-top and difficult to believe.
Theophile Gautier's Mademoiselle de Maupin is loosely based on her and is available in English via Manybooks.net. I might give it a try.