Mamizou, Kyouko, and Kogasa at the Hakurei Shrine in Wild and Horned Hermit
Mamizou is secretly called in by Nue Houjuu from the outside world to become a strong ally on the youkai side against Toyosatomimi no Miko and her faction. She arrives late however and Miko had already been defeated by the heroines. She later takes up residence at Myouren Temple.
Main article: Reimu Arc
In Reimu's story, Mamizou reveals that she crossed the sea of Sado in order to reach Gensokyo and criticizes Reimu for underestimating the vastness of the sea.
Main article: Marisa Arc
Mamizou sees through all of Marisa's lies. She also notes that her power is strong enough to be "within the top three" of the transforming tanuki in Japan.
Main article: Sanae Arc
Despite Sanae's mission to exterminate youkai, the two appear to have a friendly duel. Sanae, though, assumes that the bake-danuki is fairly old due to her language—many of the inflections and word choices used by older people in Japan resemble those used decades, even centuries, ago—and in this misunderstanding gives the youkai some encouragement. Mamizou tells her that her old language is merely a habit.
Main article: Youmu Arc
Mamizou tells Youmu that she came to give the youkai there some encouragement in their fight against Toyosatomimi no Miko. She offers to train Youmu, and after she is defeated, jokes that the half-ghost is worthy to be her apprentice. Mamizou does not appear to know about the Myouren Temple itself until Youmu explains, and finds the presence of both a youkai temple and a youkai-exterminating shrine (the Hakurei Shrine) in Gensokyo quite interesting. Mamizou invites her into the temple to rest and to talk about Sado.
Wild and Horned Hermit, chapter 9
After a strange 'black mist' assails the residents of the Myouren Temple and others, Mamizou pays a visit to the Hakurei Shrine accompanied by Kogasa Tatara and Kyouko Kasodani, suspecting Reimu Hakurei as the culprit. However, Suika Ibuki soon reveals herself as the true attacker, and the three youkai appear to leave during the chaos.
Nue Houjuu was the one to call Mamizou to Gensokyo, and they are described as being friends.
She is currently living at Byakuren Hijiri's temple.
Other residents of the Myouren Temple
Kyouko claims that Mamizou will listen to the problems and concerns of those living at the temple with open ears.