Fourteen-year-old Kathi Lehner has been growing up with her father Robert and grandmother Hedwig since the death of her mother. Her neighbor is the elderly coachman Butzbichler and his horse Dublin. When Butzbichler has to go to the hospital after a traffic accident, Dublin is to be slaughtered. Kathi and her grandmother decide to buy the horse. They find a new home for the four-legged friend - at least until they can sell Dublin again. But then everything turns out quite differently.

Flo is not quite a normal teenager: While all his friends only think about sex he can't even pronounce the word "S - E - X". But everything changes completely when one morning Flo wakes up from a strange call. His penis, excited for the first time, begins to talk to him. He claims that Flo severely neglected him for 15 years and it's time to release him.