When a certain young lady presents outstanding natural beauty, she may be termed a "McBeauty".
Has some relavence to the chat up line "If you were a McDonalds you'd be a McBeauty!" ;) Often followed by a whole lot of ignoredness...

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