Aliens go shoping

From a galaxy far away, Voltaren and Zequista travel on the speed of light and comes to earth for one purpose only, get one of the exquisites animals, a dog ,  that exist on earth, and from which his blood they will used for their peculiar sexual rite. The aphrodisiac blood exists only in few specific galaxies from the universe and our little planet happened to have plenty of dogs.  The rite brings to one of the aliens to a period of pregnancy that wich result would be, a new baby born, so know you see how important are the dogs in an alien culture.