Addendum

They can of course be mechanical wings or else made out of energy.

A Productive Plot Development

Worried about how to carry on an ongoing story? Have the main character or another major character grow wings. Think of the possibilities, and don't think of a justification, because nobody cares.

Q&A Corner

Q. Why don't more main characters have wings?
A. Cowardice.
Q. How about gills?
A. Waterworld.
Q. And antennae?
A. Antennae are failed horns.