The Book of Enoch VIII

And the spirits of the giants afflict, oppress, destroy, attack, do battle, and work destruction on the earth, and cause trouble: they take no food, but nevertheless 12 hunger and thirst, and cause offences. And these spirits shall rise up against the children of men and against the women, because they have proceeded from them.

From the days of the slaughter and destruction and death of the giants, from the souls of whose flesh the spirits, having gone forth, shall destroy without incurring judgement -thus shall they destroy until the day of the consummation, the great judgement in which the age shall be 2 consummated, over the Watchers and the godless, yea, shall be wholly consummated."