What would happen if we didn't have an epidermis?
We would essentially all die a horrible death very quickly
Think of an epidermis as a shell for a beetle, it protects the insect as the epidermis protects us. The only difference is that the shell of a beetle protects it from large unwanted predators, while our epidermis protects us very very small unwanted predators. Our epidermis is the protective layer against microbes that could potentially hurt/ destroy our vital organs.
Wouldn't you feel uncomfortable if all your organs were showing?
The epidermis also allows us humans to experience the sense of touch. Without the epidermis, we would not be able to feel pressure, temperature, or pain. You would be able to light yourself on fire and not feel pain. (DO NOT try this at home kids)