HDoom

H-Doom is a pornographic modification for Doom which replaces the game's weapon and enemy animations with, turning most monsters into nude females and adding adult animations for the Doomguy. It is currently a tech demo as of the latest version 8a build. It can be played with The Ultimate Doom, Doom II, and Final Doom. Use of the GZDoom or Zandronum source ports are required.

Bugs
The mod may crash the game if certain enemies are killed, as the kill animations have been drastically altered to be "non-lethal" and those enemies that have not been changed to have new animations will causes problems.