I think in The Artifact you go back in time and fuck your grandma and get her knocked up with your mom and aunt.
Whoa, that's almost as messed up as that Ethan Hawke movie
Predestination. In that movie, a guy goes back in time to have sex with an intersex woman and conceives a baby. She then has an op which removes her female parts and becomes a man. Meanwhile, that baby that they had was taken even further back in time by the man. This baby grows up to be the very girl whom he will have sex with and then has that op - which turns her into him. Yeah the man, the woman and the baby are all the same person. (Trust me, that was the shortest I could make the synopsis!)
Waitaminute, waitaminute maybe
Avaron1974 had it right after all when she identified this
HopesGaming preview render of a young girl posted by
ViperGts151 some 5-6 pages back:
as being the MC before his sex change op!