Not used as a sexual term.
The 'ck' loses its sharpness and becomes 'gg' and the 'g' at the end completely dissapears
Also used as an 'not-so-sweary' alternative to the word 'fucking', when talking to people like the Vicar or Aunt Agatha
See also fuggin and fugging
The man sidestepped to avoid the clowns drunken hug, causing Bozo to over balance and tumble down the large flight of stairs ahead.