Ookami runs the Souma Hot Springs and is Ritsu's mother. Like her son—the monkey of the zodiac—she's got a delicate constitution and tends to apologize constantly, even over the smallest things.
What sets her apart from a lot of other cursed Souma parents is that she actually cares about Ritsu. She even asks Tooru to be his friend, which says something. She's genuinely fond of the other zodiac members who stop by the hot springs too.
In the 2001 anime adaptation, Ookami gets a bigger spotlight. She narrates Yuki and Tooru's trip to Ayame's dress shop, though she keeps fumbling the details and apologizing for every mistake she makes along the way—which, given her personality, happens a lot.
Content compiled by AnimeList.moe from publicly available sources.