A fairy blue is a "New Conservative", popular with hardline and unalligned conservatives within the UK, the term is usually one of derision.
Came about with the UK Conservative party's redesign along with its use of lighter blues. Fairy is a pre recognised term usually used to describe males of the homosexual persuasion.
Disgruntled Tory 1: "Did you see the new party logo?"
Disgruntled Tory 2: "Sigh, he's painted the party fairy blue"
Disgruntled Tory 1: "What did you think of the blue fairy's security agenda?"