Reisen Udongein Inaba is a Moon Rabbit (Gyokuto) and a former Lunarian who fled to Gensokyo. Her original name is "Reisen," but she uses the kanji characters for "Reisen" to better blend into life on Earth. Her ability is the "manipulation of insanity." She can use her eyes to disturb an opponent's mind or show them hallucinations. Her danmaku is also unique, often featuring patterns designed to deceive the eyes. She lives at Eientei with her master, Eirin Yagokoro, and the princess, Kaguya Houraisan.

Tewi is a Youkai Rabbit living in Gensokyo who possesses the "ability to bring good luck to humans." She is the leader of the rabbits living at Eientei. Her personality is mischievous and cunning. However, she isn't just a prankster; she is said to be one of the oldest rabbits, having lived in the bamboo forest since before the founding of Gensokyo. While she looks small and cute, she is actually incredibly old.

Eirin Yagokoro is a Lunarian pharmacist living at Eientei in the Bamboo Forest of Lost. She possesses the "ability to create any medicine." She was one of the founders of the Lunar Capital. Long ago, she created the "Hourai Elixir" at Kaguya's request, which led to Kaguya's exile from the Moon. Feeling responsible, Eirin descended to Earth with her. She is calm and intellectual, though she has a slightly airheaded side. She serves Kaguya with absolute loyalty, but it is rumored that she possesses power even greater than Kaguya's.

Kaguya Houraisan is a former Lunarian princess living at Eientei, said to be the actual Princess Kaguya from the Tale of the Bamboo Cutter. Her ability is the "manipulation of eternity and the instantaneous," giving her mystical power over time. She once lived in the Lunar Capital, but after drinking the Hourai Elixir—a medicine for immortality—she became a criminal and was exiled to Earth. Her personality is innocent and full of curiosity. However, she is a bit selfish and naive, a typical sheltered princess type. She has a master-disciple relationship with Eirin and lives at Eientei along with Reisen and Tewi.

Fujiwara no Mokou is an immortal human (Hourai Person) living in the Bamboo Forest of Lost in Gensokyo. Her ability is the "ability to neither age nor die." She obtained this by drinking the Hourai Elixir and is burdened with the fate of living forever. This elixir was the same one that caused Kaguya's exile, and Mokou harbors a deep grudge against Kaguya. Her personality is solitary and somewhat self-destructive, but she is kind at heart.