Eirin

Eirin Yagokoro, commonly known simply as Eirin, is a fictional character in the Touhou Project, a long-running series of bullet hell video games and related media created by ZUN (Team Shanghai Alice). She is a moon rabbit and a renowned physician and pharmacist in Gensokyo, a fantasy land hidden from the outside world.

Her residence is Eientei, a hidden mansion in the Bamboo Forest of the Lost, where she lives with Kaguya Houraisan and Reisen Udongein Inaba. Eirin is credited with developing medicines and remedies, including the legendary immortality pills, and she maintains a private clinic for both youkai and humans. Her knowledge in biology and pharmacology makes her one of the most respected practitioners in the setting.

In the Touhou canon, Eirin is typically depicted as calm, patient, and highly intelligent, often speaking in a measured, scientific manner. She appears in several games and related media as an ally, mentor, or boss character, and she is frequently referenced in fan works and discussions about the series.

Beyond Touhou, Eirin Yagokoro is a fictional name; the given name Eirin is based on kanji 永琳, and the surname 八意 (Yagokoro) is the in-universe family name. The name is used primarily within Japanese-language media and fan communities.