It means “pas”, to give “L’amour c’est pas propre.” The point of the “pô” is that it gives an accented colour to that sentence, somehow to avoid direct responsability of the locutor for the (questionable and grammatically incorrect) sentence.
“Pô” means the same thing as negative particle “pas” but has a limited usage, as it is not a widely accepted norm of pronunciation. In France, this phenomenon is particularly prevalent in the north (Brittany and Normandy) and it is heard everywhere around Canada. This phenomenon is due to a natural vowel reduction (phenomenon also responsible for the fall of the final vowels that led to the appearance of the French “e caduc”) which still relevant in the north of France and in Canada.
Hope this information was useful.