Mahiro Yasaka's mother, who also happens to be a real, part-time deity hunter.
Yoriko Yasaka first shows up in the anime, Nyarko-san: Another Crawling Chaos. She has a son in high school named Mahiro, though some doubt it because of her young appearance. She reveals herself as a deity hunter (only part-time) who has been on the job since her college days. Despite being a hunter, she welcomes Nyarko, Cthugha, and Hastur into her home, seeing them as friendly aliens who are tasked in protecting Mahiro from danger.
Like her son, she uses forks as her weapon of choice, though she is more proficient at it due to her deity hunter career. Like Cthugha, she enjoys playing video games, and both characters are able to bond through multiple game platforms Yoriko buys home from her travels. She also has a habit of hugging her son, claiming to be replenishing her "sononium."