I want to teach a self defense class for women

I always have this fantasy about teaching a self defense class for women. I would be the only man in the room and I would ask the women to take turns demonstrating the quickest techniques for immobilizing a male aggressor. This would involve them in some way making physical contact with my testicles, whether by kicking, stomping, kneeing, punching, or grabbing. The most optimal method for any given situation would depend on the position of the male aggressor in relation to the female being assaulted. For example, if she was being attacked from behind, a hard grab would be more than sufficient; if she was seated and a male approached her in close proximity so that a kick would be impractical, a hard knee might just do the trick instead.