Rev 9:1 And the fifth heavenly angel sounded, and I saw a star fall from the heaven to the earth and to him was given the key of the bottomless pit.
Raphaim were the giants and the Nephilim were the angels who refused to be born again, and instead left their proper habitation and just mixed with women.
These angels were locked up in chains by YHWH until judgment day. We learn from ancient history that these giants became the demonic spirits that still trouble people today.
