In 1994, when I was a child, Mattel released Tropical Splash Ken, a blond-haired and blue-eyed hunk in board shorts and nothing else but a fragrance. The box shouted, “Ken is scented!” And indeed, he was: floral with a hint of plastic, like a glossy, fake bird of paradise. Of all my dolls, this perfumed one was my favorite, my top pick for my Barbies whenever they needed a hot date. As I got older, my olfactory palate, and tastes in playmates, became more discerning, but the connection between Ken’s aroma and his desirability remained evidence of a seldom-discussed truth: Smell and courtship are inextricably linked.