https://en.wikipedia.org/wiki/Nephilim
The New American Bible commentary draws a parallel to the Epistle of Jude and the statements set forth in Genesis, suggesting that the Epistle refers implicitly to the paternity of Nephilim as heavenly beings who came to earth and had sexual intercourse with women.[34][c] The footnotes of the Jerusalem Bible suggest that the biblical author intended the Nephilim to be an "anecdote of a superhuman race". Superhuman, in this context, refers to the extremity of their wickedness.[d]
Some Christian commentators have argued against this view, citing Jesus's statement that angels do not marry.[36] Others disagree since Jesus also compared angels to men, thus implying the former's ability to have sex.[37] Angels are also never explicitly described as being incapable of marriage. The absence of marriage among angels can be thus compared to willful celibacy.[38]
Every time I take a peek into the world of christianity, it looks like a ton of infighting about definitions of who exactly had sex with who, when, how, and why.