Remember when Jesus said and many in the Evangelical community use. Let it be established by two or three witnesses, which I've given, OT procreate after it's kind, Jesus said angels do not marry or are they given in marriage and the epistles Paul tells about heavenly bodies and earthly bodies, how they are not the same. Which goes to, after it's own kind, it's impossible for angels and humans to procreate.
Mules are made from mixing kinds of animals. Mixing different kinds was forbidden in the Torah. It was forbidden, not impossible. Ligers and Tions have been bread as well. Zebras have been cross-bread with horses or donkeys.
Matthew 22:30 tells us "At the resurrection people will neither marry nor be given in marriage; they will be like the angels in heaven."
The angels in heaven do not marry or reproduce.
But in Jude, we read of angels that sinned that did not keep their proper abode, which we might assume was heaven. The angels in heaven do not marry or give in marriage, but these angels were not in heaven.
Jude
6 And the angels who did not keep their proper domain, but left their own abode, He has reserved in everlasting chains under darkness for the judgment of the great day;
II Peter 2 mentions the angels that sinned as well:
4 For if God spared not the angels that sinned, but cast them down to hell, and delivered them into chains of darkness, to be reserved unto judgment;
5 And spared not the old world, but saved Noah the eighth person, a preacher of righteousness, bringing in the flood upon the world of the ungodly;
6 And turning the cities of Sodom and Gomorrha into ashes condemned them with an overthrow, making them an ensample unto those that after should live ungodly;
7 And delivered just Lot, vexed with the filthy conversation of the wicked:
Notice the sequence, angels sinning, the flood, Sodom and Gomorrah and Lot. This is the sequence of events in Genesis, the sons of God and daughters of men passage, the flood, and then Sodom and Gomorrah.
If a group of angels fell with Satan and became demons, then who are these angels who sinned before the flood who were already bound and reserved to judgement? Why wasn't Satan already bound at this time if he was a part of the group Peter speaks of here?