Ёрико Ясака

Mahiro's mother. A monster hunter who started her career in college. She looks young, making it difficult to assume that she has a high school-aged son. She hid her part-time job until she discovered aliens in her own home. She tolerates them, allowing Nyaruko, Kuuko, and Hastur to live in her house. She insists that Nyaruko slow down the development of her relationship with Mahiro, but not as strongly after being rescued. She uses forks as a weapon, but is more skilled and uses more of them than Mahiro. Yoriko is obsessed with video games and stockpiles game consoles. Additionally, she has a habit of hugging Mahiro, claiming that it replenishes her made-up element "Synonium" in her.