this phrase describes sex in the famed doggy position that is so brutal and frenzied that it could be said that the build up of internal pressure caused by each vigorous thrust could in fact cause the "victim's" kidneys to in fact "pop"

Noun: a friend who is usually only called upon by a friend when a more primary/prominent friend is unavailable.

Taken from the term “second string” in an athletic competition situation. In football, if the star quarterback gets injured during a play, the second string is called off the bench to replace him/her. A “Second String Friend” is essentially benched until needed, if ever.

Synonyms: Plan B, Second Choice, Secondary Friend, Benched Until Needed