Define Twelfth Base Meaning

Twelfth Base

WTF ARE THERE EVEN THAT MANY THERE ARE ONLY 3 IN BASEBALL

guy a: dude, i did it w/my gf
guy b: how much?
guy a: twelfth base
guy b: wtf

By Laverna

Twelfth Base

Fucking a girl so hard she dies.

Steve: Man I fucked Katie so hard last night that she died while cumming.

Aneesh: Really, twelfth base? How was her funeral?

Steve: I got to thirteenth base at it.

By Kalie