The Steam-Version of HuniePop is censored.
To uncensor the game, do the following:
a) go to the directory where you've installed the Steam-version, eg:
b) create an empty file named "huniepop_uncensored_patch.game", eg:
c) That's it! Start the game.
You'll now read in the main screen (right beneath the version number in the lower left corner) the word Uncensored. Enjoy!
Hint: The GOG-Version is not censored.