Filthy Henry: The Fairy Detective - Filthy Henry, #1

Filthy Henry is Dublin's first and foremost fairy detective. Something of a niche job since most people do not know that fairies are even real, let alone need a detective. But when The King of the Leprechauns has his crock of gold stolen by some humans he requires the services of a detective. Lucky for him Filthy Henry is just the man he needs. The only problem is nobody in the world can stand him.
Which does not really bother Filthy Henry as he is not too fond of the world either...