This character is Pessimal's invention and has no canonical status.
In the Pessimal Discworld:-Edit
Graham Blakeney is a contemporary of Alice Band and a Licenced Assassin of unique style and approach. He could be fairly described as a very gay blade.
A former legal clerk before being invited onto the Mature Students Class, Graham now works as an administrative PA for the Dark Council of the Assassins' Guild. He is entrusted with taking Council minutes and providing secretarial service for Lord Downey. He is therefore for Downey what Drumknott is to Vetinari. He has taken on contracts to inhume, but in much the same spirit that the cutourier Pepe will cease to be his usual reasonable friendly self if confronted with a dangerous homophobe and gay-basher. He adores Alice Band for bringing him out of his closet and showing him he is capable of inhuming, in the right circumstances.