Okay, so now that you've brought it up--I've never understood "nephilim". Who are they? From where did they come? They are mentioned several times in OT. In my reading I've always thought they were human, but now you are mentioning them in the angelic realm. My brain is spinning--HELP?!?
Hopefully this isn't too off the beaten path for this thread, but: In Genesis 6:4 the Nephilim are introduced as being the offspring of the Sons of God and the Daughters of Men; sons of God being an identifier for angels in Job. Somehow or another they survive the flood and are around to take over the land of Canaan and produce creatures like Goliath. It isn't inaccurate to call them human, but neither does being human tell the whole story. The particular tribes that harbored the nephilimic bloodlines were later ordered to be utterly annihilated by God, not just subjugated or driven out.
The book of Enoch (1 Enoch) says: But now the giants who are born from the (union of) the spirits and the flesh shall be called evil spirits upon the earth, because their dwelling shall be upon the earth and inside the earth. 9 Evil spirits have come out of their bodies. Because from the day that they were created from the holy ones they became the Watchers; their first origin is the spiritual foundation. They will become evil upon the earth and shall be called evil spirits.