You have to be a good judge of character and willing to spend time getting to know people before you sell them a puppy. No - on both counts. Sex in animals is governed by hormones. There is no love, emotion or thinking involved. The experience is forgotten once her season is over.
Males only think about sex when they're near a bitch in season.
He'll become more territorial and aggressive toward other dogs, may lose his house manners, and will become uncontrollable if there is a breedable bitch in the neighborhood. There is no truth to the old wives' tale that bitches need to have a litter before spaying. Research shows that even baby puppies may be spayed or neutered with no ill effects. Spaying a bitch before her first heat cycle eliminates the risk of breast cancer and life-threatening uterine infections. In fact, neutering will make him a better, more trainable pet by allowing him to channel what used to be sexual energy into other areas.