Sometimes the monster doesn't show up :(
Viewing post in Stuck In Space (18+) comments
Strange. In all my testing I've never had that happen. If you're near the end of the game (when the director shows up and after you've triggered her cutscene) between her and the doctor, it's possible that they keep the poor alien stuck in his lair from the constant sex scenes.
Either way, reloading the game should fix any issues like that.