I put hand sanitizer around my groin anus area and it really burned. i also tried putting cologne and other things and it always burns. why sensitive?

The surface cells: or epithelium of the scrotum/anus in men and perineum in women are non-keratinized. The external layer of keratin present in most epithelial cells provides somewhat of a water barrier. Without this keratinized layer, the numerous nerve endings present are exposed to the environment. Remember, this sensitivity has a lot of benefit when it comes to pleasurable intimacy. Stay well:)