The word 'femdem' is an adaptation to words, commonly used by 'Rudeboys' or 'Ghetto brehs' in London, such as Mandem or Gashdem.
Femdem means a female that a person could either be friends with, or a female that someone has only just met. Mainly used by males, and usually from one male to another.
Femdem and gashdem both mean a the same thing. Except Femdem is generally looked upon as a less vulgar word, because the word gashdem could be referring to the female genitals and could be look upon as degrading to females. Fem is merely a reference to the word 'female', as mandem refers to the word 'man'.
'Fem' - Abbreviation of Femdem
Also can be known as Femdemerage, femdemerige or Femage
My man hooked me up with some hot fem the other day.
Yeh, i called the mans and some of the femdem over.
I was with some buff femage last night.