Humphrey would take some confidence and swagger to pull off, and in agreement with the others, it has strong teasing potential. A dog that used to stray around my area received the nick name
Humphrey because of his avid pursuit of female dogs. He was also less subtly called Hump-freely.
Nikita is a fun upbeat name for girls. For a boy, I prefer
Niketas since it's less ambiguous and won't be mistaken as feminine.