A term that can basically be used to describe anyone. Most commonly it is associated with homosexual men or men wearing strange clothing, though this way is not always an insult, simply an observation. It is very rarely associated with women, despite actual Dew Fairies being female. Anyone prancing about or dancing can easily be called a Dew Fairy. It is an insult but not exactly a serious one.
Other words that are associated with this are:
Doo Fairy (As in feces)
'Doo Fairy (As in Scooby Doo)
Do Fairy (As in doing things)
'Do Fairy (As in Hairdo)
Due Fairy (As in being due)
The nice thing about this insult is that it can be translated to any of the others without the person knowing, so an insult can be transferred into a compliment should your boss accidentally overhear you calling him a Doo Fairy or Dew Fairy. Simply switch to Do Fairy, and explain that you were simply saying he does a good job at doing his work, etc.
This insult is otherwise seen in the eyes of the beholder and can be translated however you'd like.
That guy is such a Dew Fairy. Just look at how he walks.