Keiko Yukimura (雪村 螢子, Yukimura Keiko, English manga: Keiko Yukimura, English anime: Kayko Yukimura) is Yusuke's childhood friend and classmate. She has known Yusuke for many years and acts as a parental figure, often trying to get him to attend his classes and behave, though usually to no avail. Yusuke attempts to keep his job as spirit detective a secret from Keiko though she finds out about it during his third case, as the Saint Beasts end up using her as bait to anger Yusuke. Keiko worries about Yusuke but knows that he is more happy fighting demons than having a normal school life. She is noticeably upset when Yusuke leaves for the demon plane in the final story arc but waits for him after he promises to return so they can get married. At the end of the manga, Keiko begins to go to college to be a teacher. In the anime television series, Keiko is voiced by Yuri Amano in Japanese and Laura Bailey in English. Keiko is author Togashi's least favorite character in the series due to her being a "typical" manga character.