The worst that can hit you at all in steam is either a VAC ban (anti cheating system possibly shutting down account) or a copyright claim.
im pretty sure this kind of stuff can work there, and if not, well, one game named "succubus affection" had a nsfw patch outside of steam because the steam version was censored.
So, unless copy right claims or VAC does something, if the game gets through steam greenlight, it can be released.
Well, we just might have to see if Valve pulls a Valve Move.