The Guardian Beast Devoted to Shintoism and Buddhism.

"I've been protecting shrines and temples from simple enemies all the time until now. It's, like, volunteer work?"

Aunn appears as the Stage 3 Boss in Hidden Star in Four Seasons. She is a komainu youkai who guards places of religious worship. This includes the Hakurei Shrine, even though Reimu was unaware Aunn was protecting her shrine until Hidden Star in Four Seasons. Ironically, Reimu beats her up for intruding.

She is content with guarding sacred places, considering it a kind of "volunteer work".