Eirin Yagokoro


Brain of the Moon

Eirin Yagokoro's usual outfit. It is navy blue and vermilion in color.

Patron Saint of Learning

Eirin made this costume based on the customs of the outside world. Apparently, this is what a patron saint of learning wore...

Genius Doctor in the Bamboo Forest

A costume that Eirin sometimes wears for work. It is said to be available at Kourindou.

White Sage of Wisdom


Brain of the Moon
Voice Lines
Temperament: Gengetsu

Gengetsu (a Touhou LW original) refers to an optical phenomenon where two bright spots of light appear in the sky on either side of the moon, caused by the moonlight refracting through ice crystals suspended in thin clouds. These bright spots are called moon dogs. This illusory moonlight is an apt temperament for Eirin, who once created a fake full moon in the night sky. Eirin is endowed with Fire Phase, as her medicine is effective yet bitter, and Moon Essence, with her vast intellect.

Ability: Capable of making any drug. Natural genius.

She displays this ability for the people of the Human Village that visit Eientei. She may have only revealed a tiny portion of her many abilities, but this is to maintain the peace that she has attained on the earth. The ability to create medicine supports her daily life with Kaguya and the others. When compounding medicine, she sometimes borrows the abilities of others, as was the case with the Hourai Elixir, which she made by borrowing Kaguya's ability to manipulate eternity. She can also create medicine like The Ultramarine Orb Elixir, which is impossible to make with the technology available on the earth. The regular samples she receives from Medicine Melancholy allow her to develop new experimental drugs. Her knowledge of medicine is not limited to just the formulation of drugs but also extends to medicinal practice, making her a pharmacist and a doctor. She has even been witnessed performing surgery on multiple occasions.


Arrow Siege

Eirin Yagokoro's Spread Shot (a Touhou LW original). She traps her target in a circle of advancing bullets. Eirin is only a pharmacist at Eientei, but on the moon she was a sage. Her Brain of the Moon epithet marks her out as special even amongst the other Sages of the Moon. It is believed that she was in charge of the Lunar Capital's policies and military strategy.

  • Vector Bullet
  • Anti-Moon Defensive Arrow
  • High Vector Bullet
  • Anti-Moon Guardian Arrow
  • Vector Maneuver Bullet
  • Anti-Moon Defiance Arrow
Gold God Web

Eirin Yagokoro's Focus Shot (a Touhou LW original). A net of lightning as fine as a spider's web rains down on her targets. Eirin can create even rare natural phenomena whenever she wants, wherever she wants... This god-like power is apparently relatively commonplace in the Lunar Capital. These powers are made possible through the use of precise and delicate instruments and mechanisms. Perhaps Eirin's bow is what gives her this power...

  • Energy Net
  • Lightning Rod
  • Dense Energy Net
  • Lightning Rod Arrow
  • Concentrated Energy Net
  • Lightning Net
Curse of the Heavens: Apollo 13

Eirin Yagokoro's Spell Card. She attacks with a foreboding curse. In the outside world, there was a mission to land on the moon that failed. It is said that the Lunarians know why...

  • Curse of the Heavens Arrow
  • Anti-Moon Offensive Arrow
  • Forbidden Arrow
  • Forbidden Magic Arrow
  • Anti-Moon War Arrow
  • Taboo Arrow
Revival: Seimei Yuugi -Life Game-

Eirin Yagokoro's Spell Card. She attacks by creating an array of cells and leading them to extinction. Life games are a simplified simulation of a group of life forms and could be interpreted as a metaphor for the highly regulated society of the Lunar Capital. However, the dwellers of the Lunar Capital have extended their lives to where death is no longer an issue, so perhaps they have already broken the rules of the game...

  • Stem Cell Bullet
  • Birth Bullet
  • Survival Bullet
  • Overpopulation Bullet
  • Next-Generation Cell Bullet
  • Underpopulation Bullet
Heaven Spider's Butterfly-Catching Web

Eirin Yagokoro's Last Word. She weaves a web of light in the sky, preventing her targets from escaping. An ancient Chinese philosopher once said, ''Heaven's net casts wide. Though its meshes are coarse, nothing slips through.'' Heaven's net is like the strict regulation over the Lunar Capital society, where all sins are laid bare and no evil escapes. This society could be considered a realization of the axiom ''the greatest happiness of the greatest number is the measure of right and wrong.'' This Last Word may have some connection to how the moon emissaries' primary mission is to survey and monitor the earth, which now includes observing Eirin, who was once an observer herself.

  • Electric Surveillance Net
  • Anti-Moon Defensive Laser
  • Electric Communications Net
  • Anti-Moon Offensive Laser
  • Electric Analysis Laser
  • Electric Capture Net


Skill: Diluted Ochimizu

Miraculous water that is said to bring back youth. Eirin must have a good relationship with Lord Tsukuyomi if she has this in her possession.

Skill: Moon Intellect

The vast intellect of the Brain of the Moon. Is there any being in existence who surpasses her intelligence...?

Skill: Golden Pill Fragment

A miraculous medicine of long life created by refining minerals. However, the same medicine created through Chinese alchemy on earth is said to be poisonous...

Passive: Panacea Pharmacist
Passive: Intellectual Study
Passive: Fake Full Moon