Over Sexed rugsuckers from mars (1989)

Aliens return to earth after 10 million years to see what has become of the human experiment they have created only to be disappointed by what they find. After landing they come upon Vernon a homeless bum and decide that earthlings are untidy and figure crossing a vacuum and a human will elimate the problem as well as create a better race of beings. The experiment however goes awry after one of the aliens pee in Vernon's bottle of gin which makes him insanely in love with the vacuum Dusty which was brought to life by the aliens. Things get a tad bit crazy from here as Dusty tries to reproduce and Vernon tries hard to find Dusty.