"It happened after the sons of men had multiplied in those days, that daughters were born to them, elegant and beautiful. And when the angels, the sons of heaven, beheld them, they became enamoured of them, saying to each other, Come, let us select for ourselves wives from the progeny of men, and let us beget children."Enoch is of course not part of the recognized Biblical canon for most, but this passage really just expands on Genesis 6:4. Historical the term was glossed as "giants," so D&D goliaths would work, but that may be a too literal reading. They're demigods so half-Celestials? Tieflings? Keeping Tolkien in mind, the race that stood between supernatural beings and mundane men, were elves, so I think elves presiding over the pre-Flood world fits nicely. They can be taller than humans in true Tolkienian fashion, too.
- Book of Enoch, Book of the Watchers
This is not necessarily a new view. The internet tells me that the late thirteenth-century South English Legendary and some Icelandic folktales explain elves as angels that sided neither with Lucifer nor with God.
Children of Cain (Qéní)
Cain (Qayin) may be glossed "spear," but it is a cognate to a mid-1st millennium BC South Arabian word meaning "smith." Cain's descendant Tubal-cain is described in Genesis 4:22 as a "forger of all instruments of bronze and iron." Perhaps the Mark of Cain was the stature and coarse features of his dwarven descendants? Ray Winstone as Tubal-Cain in Noah has the beard, too:
Lillith is now considered the first wife of Adam, but the term was originally glossed in Hebrew text translations as "night monster" or "night creatures" and appears in a list of animals in Isaiah 34:11. The term (likely the name of a demon) derives from the Akkadian lilitu which was the female version of the lilu demons. Perhaps the lilu creatures of the night are goblinoids with Lillith being the Goblin Queen?