Ketsuno Seimei is the head of the Ketsuno clan and widely regarded as the strongest onmyoji in its entire history. He's the older brother of Ketsuno Christel.
By all accounts, Seimei is a genius—disciplined and driven, though his tough exterior hides genuine concern for his sister. He worries about her more than he'd probably admit.
These days, Seimei's main job is keeping Edo and the Bakufu safe. He does this through divination and foresight, catching disasters and bad omens before they become real problems. To pull this off, he's deployed over 1000 shikigami throughout Edo as his personal surveillance network. They feed him constant information, which he processes to figure out which way the nation is heading and what the Bakufu needs to do about it. It's a heavy responsibility, but apparently no one else could handle it.
Content compiled by AnimeList.moe from publicly available sources.