One of the many characters in the Touhou Project, she is a human who became immortal after drinking the Hourai Elixer, and is the bitter rival of Kaguya Houraisan. She appears in Touhou 8 Imperishable Night as the Extra Stage Boss. Nothing can kill her. Mokou has the ability to control fire, and her pants and hair have wards attached to them to prevent her from being damaged by it. She comes from an aristocratic family.