'To be satiated,' as in Revelation 19:21, signifies being nourished by lusts and taking delight in them.

(Verweise: Apocalypse Revealed 837)

837. And all the birds were filled with their flesh. This symbolically means that by their lusts for evil, which they had made their own, they fed, as it were, the demons of hell.

Birds symbolize falsities emanating from hell, and because caught up in those falsities are demons of hell that are present with a person in his falsities that are products of his love, therefore these demons are here symbolized by birds. A person who is caught up in such falsities also becomes such a demon after death. That useless and harmful birds, especially unclean and rapacious ones that feed on carrion, symbolize falsities that are products of a person's love, may be seen in no. 757 above.

Flesh here symbolizes the evils attendant on the lusts that are inherent in a person (no. 748). To be filled with that flesh means, symbolically, to be as though fed by those lusts and to draw them in with delight. For the demons of hell that are caught up in the same lusts for evil eagerly inhale and fill their nostrils with them, and with the life attendant on them, because of the lusts emanating from these people's thoughts and respiration, so that the two also live and dwell together.