There's both an R and an X-rated version of this but in reality neither one is all that hardcore from what I've seen. In 1974 though I imagine all the pubic hair, tits and sex talk was a bit shocking in a big budget film. There's gotta be the best special FX in any"adult" film on display here including stop-motion animation featuring an homage to Ray Harryhausen's skeleton warriors from SEVENTH VOYAGE OF SINBAD(a young Rick Baker was involved here). It's also a pretty entertaining ride including rape-robots, a penis-shaped spaceship, a doctor named Jerkoff, Candy Samples playing an evil hook-handed baddie and people having spontaneous orgies due to a sex-ray from outer-space. Obviously nothing is taken very seriously here and I think that works and even though I generally hate spoofs I've rewatched this one many times over the years and always had a good time.
There was a sequel made almost 20 years later, called FLESH GORDON MEETS THE COSMIC CHEERLEADERS, which I sorta recall seeing, possibly on some late-night cable channel, but I don't really remember anything about it which says a lot.
Released in 1977 in Japan as SPACE WARS! Very sneaky!: