(here via metafandom)

There's another dub-con scenario, one which I've almost never seen in fanfic: the scenario where one partner genuinely has no idea that the other isn't freely consenting to the sex.

I've actually seen this done a couple of times in SGA fandom - neery's Foolproof and Incapable of Error is the best example I can think of. It's quite rare, though, I agree.