Sigui works as both a nun and an inquisitor for the Pope's central office, tasked with rooting out and executing heretics. She's known for her unwavering devotion to God and her absolute refusal to compromise on matters of faith—which makes her come across as harsh and unforgiving to most people. Though plenty call her cruel, she genuinely believes she's doing righteous work. The real problem is that she's too rigid, too serious, and far too quick to judge anyone who doesn't fit her strict worldview.
She's particularly obsessed with taking down the Rebel Army, viewing them as nothing more than heretics. Their leader Annelotte especially infuriates her, since Annelotte carries demon blood and Sigui sees that as an abomination. Alchemy is another major hang-up for her—she considers it outright heresy, even though the Pope's own office can't agree on whether it actually is.
In combat, Sigui wields the Holy Flame Mace and God's Chained Blade, and she's skilled enough to go toe-to-toe with Annelotte. She channels divine power through what's called "Holy Poses"—essentially God's miracles made manifest—similar to how Melpha operates in Queen's Blade. Her fighting ability backs up her conviction that she's on the right side of things.
Content compiled by AnimeList.moe from publicly available sources.