Sara Gilbert (Leslie Winkle)
Leonard and Leslie have so much in common that it’s a wonder their relationship didn’t last longer than a single episode. Both are employees at Caltech, and they both work in the field of experimental physics. The show’s writers admitted to introducing Leslie as a female version of Leonard, even going as far as giving her glasses, curly hair, and the same weird apparel.
After Leonard and Leslie’s short-lived relationship, Howard comes in to sweep her off her feet. Well, at least he tries to. People mainly know Leslie not as the female Leonard but as Sheldon’s archnemesis for all of nine episodes.