Yggdrasil (ユグドラシル, Yugudorashiru?) is the heavenly computer system that maintains reality, with the Gods and Goddesses acting as its programmers, system administrators, and debuggers. Yggdrasil works with the Goddess Relief Office by notifing the goddesses such as Belldandy working at the office of people whose fortune and misfortune is out of balance given their actions such as fortitude in facing misfortune, kindness in sympathizing with others. Each person Yggdrasil chooses is granted one wish which can be anything ranging from "wealth that would last a life time" to the destruction of the world, or even for simply a "Girl like you".

Chrono, Ere, and Ex are three goddesses who maintain Yggdrasil.