In medieval Jewish folklore, Lilith was seen as the queen of the demons who taunted Adam (and his sons) at the dawn of time with sexual desire, and who also killed newborn babies. She was seen as a dangerous succubus associated with sexual temptation, storms, disease, illness, and death.
The existence of demons was a common belief in Mesopotamian culture and Babylonian civilization. Since the Jews spent 50 years in captivity in Babylon, they were indirectly deeply influenced during this time by their captors' beliefs in demons. Eventually, the Jews adopted some of the Babylonian demons (including Lilith) into their own nascent system and hierarchy of demonology.
While the Unification Church does not affirm the existence of Lilith, it does teach that sexual lust was at the heart of humankind's fall from the original creation. Such sexual sin was said to have been incurred between Satan and Eve, not between Lilith and Adam. Nevertheless, the theme of sexual corruption is the common thread that unites these two views of the creation account. Thus, Unification theology actually acknowledges the existence of demons and evil spirits but they are understood as a natural part of the created order, whose torments may serve a greater purpose. As per the Divine Principle:
Let us examine the returning resurrection of evil spirits. In the Bible we read about the "cursed," who are liable to "the eternal fire prepared for the devil and his angels." (Matt. 25:41) "His angels" here refers to evil spirits who live and work under the control of the Devil. The spiritual creatures commonly known as ghosts, whose features and identity are often unclear, are none other than evil spirits. Even evil spirits are able to receive the merit of the age by returning to the earth. However, the works of evil spirits do not always bear fruit and result in their receiving the benefit of returning resurrection. To receive such benefit, their works must have the effect of punishing earthly people to help them make conditions to indemnify their failures, which have frustrated God's past efforts to cleanse them of their sins. How, then, can the works of evil spirits result in casting judgment on behalf of Heaven?
The works of evil spirits may help an earthly person fulfill indemnity conditions to purge his sin in two different ways. First, the spirit may trouble the earthly person directly. Second, the evil spirit may descend to the spirit self of another person living on earth who is about to commit a sin comparable to the sin of the person to be punished, and work through the second person to attack him. In either case, if the earthly person gratefully and willingly suffers the work of the evil spirit, he will make the indemnity condition to purge his and his ancestors' sin. This sin will then be resolved, and he will enter the higher sphere of benefit, which has become available in the new era. Thus, the works of the evil spirit will have cast judgment on the person for his sin on behalf of Heaven. Consequently, the spirit will receive the same benefit as the earthly person; he, too, will enter the higher sphere of benefit (I.18.104.22.168).
Furthermore, the evil spirits themselves are not seen as wholly or irredeemably evil. Instead, they are understood to play a role in the gradual moral perfection of the universe, and thus are also able to advance spiritually once they successful cause an individual to purge their sinfulness.