Heavy Petting (2007)

When Charlie meets Daphne - the girl of his dreams - he never expects he'll have to battle past her pet dog "Babydoll" to woo her. And just when it seems he can't beat the beast and all is lost, something unexpected happens: Charlie begins to fall in love with the dog himself, realizing he never really needed a girlfriend in the first place. Now, in order to keep hanging out with "man's best friend", Charlie must scramble to keep the relationship with Daphne going at all costs - or risk losing them both.