It's been a long time, but it seems like Cordelia had a benign or even helpful one in her apartment after she moved from Sunnydale to Los Angeles in "
Angel". If only every TV series that got cancelled on a cliffhanger also received a canon comic book guided by the showrunner, to wrap things up.
Angel: After the Fall
Definitely has a folkloric precedent:
"A house spirit (or household deity/guardian) is a benevolent entity from folklore believed to protect a home and its inhabitants, often assisting with chores in exchange for offerings like milk or bread, but can become mischievous or leave if disrespected. Common examples include the Slavic domovoy, Scottish brownie, and Roman lares, embodying ancestral spirits or nature spirits tied to a place, residing near the hearth or in liminal spaces. These spirits bring good fortune, but neglect can lead to trouble, requiring offerings or respectful care to maintain harmony."