Jill used to be called Alektra Maria von Levenherz back when she was the First Princess of the Galia Empire. Everyone thought she'd died from illness as a kid—she was only 10 at the time. Turns out that wasn't exactly what happened. Now, at 29, she's running Arzenal as its Commander-in-Chief, and she's also a pilot herself. Her right arm is artificial.
She's a Norma genetic type and the daughter of Galia Emperor. Despite her royal background, she's deeply connected to Arzenal and the work they do there, which is pretty far removed from typical imperial life.
Content compiled by AnimeList.moe from publicly available sources.