10th base is simple. It comes after 9th base, which is anal sex whilst strangling the person, so therefore 10th base is simply death. However, You have the option to have sex with the dead body or just leave it.
"Hey mate, u won't believe it but I finally got there..10th base action last night"
"Omg, trevor, I was joking. You just killed someone"
When you get to home base twice in one evening, then have a threesome with said two previous people.
Danny seduced two separate chicks, man! Then got to play with them together! Holy crap, he's the first in our college to get to 10th base! We must worship him.
It is said of the situation where a person has the bad luck to make contact with his testicles against an undefined surface or object, intentioned or not.
Given the nature of the word, it is more appropriate to design cases where the interaction is made with a moving object, for example, a ball.
Although it is extremely painful for the victim, it tends to be considerably funny to people who witness it.
Today in the baseball game the pitcher took a nutshot; the baseball hit him in the nuts.
Man, I just watched the funniest nutshot video ever.