a nancy boy can cover three different people but the top one is the most important term.
1. a very feminised man (the original meaning)
2. but today it's used as a term for a gay guy too.
3. it can also be used to describe a boy on the transition to a girl.
it's most used by the British and the phrase most likely originated from either Manchester or Liverpool.
An extremely insulting and degrading term for a homosexual man, especially one whose behaviour, appearance or voice is considered to be extremely soft, effete, and feminine. By extension, you can describe a man who is effeminate or lacking bravery, especially he likes shaking his fucking asshole.