The Eidu were an evil sect of monk-like vampires who worship the Master. Their perversion of religion was only exceeded by their perversion of their own selves. They believed the Master had given them the legacy of second sight. To become Eidu, young acolytes, still human, were brought to the monks and tortured. They were made to beg for the blood of everlasting life. The final ignominy wa that once they had begged for life in death, they had to burn their own eyes out. Only then they were they bitten and turned.

    Stationed in Japan, the Eidu served one of the Master's acolytes: the Slayer-turned-vampire Yuki Makumura. After the Master was slain by Buffy the Vampire Slayer, the Eidu congregation waited nearly almost five years for their plan to reach fruition, at which time they ventured to Sunnydale to resurrect him. During the resurrection ceremony, Yuki and the congregation were all usted by Buffy and the Scooby Gang except for one. Only seven members of the Eidu have been revealed so far; whether more of the congregation exists has not been revealed.

The Eidu exhibit the normal vampire attributes such as unholy strength and the ability to draw blood from a person's neck by biting them.

The Eidu have all the vulnerabilities of a Buffyverse vampire: direct sunlight will cause combustion that would eventually kill them if they stay out in the sun's rays for more than a few seconds. A stake through the heart and decapitation would instantly kill them. In addition, certain objects of religious significance to Christians -- specifically Bibles, crucifixes, and holy water -- can burn their flesh.