Pants with the top part of a pair of boxer shorts sewn in to them so they are always exposed.
No they are not a full pair of underwear either.
It is like somone cut off about the first 5 inches of a pair of boxers and then sewed them in to the top.
This way even if you pull your pants up your underwear are completely exposed.
How fucking rad.
We are devolving faster and faster ... the end of the world is near.