A.J. Raffles? Thomas Carnacki ? As I began reading The League of Extraordinary Gentlemen: 1910 I was scratching my noggin. I had missed the previous installment and well known characters like The Invisible Man were gone. I checked Bookgasm’s review and Rod Lott suggesting “research those characters on Wikipedia beforehand.” So I clicked over to the Wiki bio on the fictional Raffles:
Arthur J. Raffles is a character created in the 1890s by E. W. Hornung, a brother-in-law to Arthur Conan Doyle, the creator of Sherlock Holmes. Raffles is, in many ways, a deliberate inversion of Holmes — he is a "gentleman thief," living in The Albany, a prestigious address in London, playing cricket for the Gentlemen of England and supporting himself by carrying out ingenious burglaries.
The model for Raffles was George Ives, a Cambridge-educated criminologist and talented cricketer according to Lycett. Ives was a discreet gay, and although Hornung "may not have understood this sexual side of Ives' character", Raffles "enjoys a remarkably intimate relationship with his sidekick Bunny Manders."
So being a history buff I kept investigating. And if you're interested, the Ives bio is here. Cheers!