The most logical conclusion is that the word demon is simply another title or name for fallen angels.However, this view, like the previous two, is without the slightest Biblical support.
They are the spirits from the unnatural union between angels and women in Genesis 6.The Bible declares that Adam was the first man (1 Corinthians 15:45). But there is no scriptural support whatsoever for this view. They are spirits of a pre-Adamic race.However, this cannot be, for the Bible declares the unsaved dead are in Hades and not roaming the earth (Psalm 9:17 Luke 16:23 Revelation 20:13). They are spirits of deceased wicked men.There are a number of suggestion origins of demons, with the most logical being that they are fallen angels. Theories Surrounding the Origin of Demons Christ demonstrated His power over demons and, furthermore, He gave His disciples power to cast out demons (Matthew 10:1). In Jesus Christ’s teachings and ministry He often confronted demons and their activities, i.e., demonic possession of individuals (Matthew 12:22-29, 15:22-28, 25:41 Mark 5:1-16). In each case it is translated by the word devil in the King James Version. The word for demons in the Greek language is daimon and is found more than 75 times in the Greek New Testament.
We know from certain Scriptures that Satan fell from heaven and other angelic beings (demons) shared in Satan’s fall and became evil ( Ezekiel 28:18 Matthew 25:41 Revelation 12:4). Satan’s evil angels are known in Scripture as demons. The Bible provides abundant evidence of the existence of demons.