My twitter handle is @TheRealRevK but the name is RevK which I use extensively since I signed up as a reverend with ulc.org many years ago. I use it in a lot of places, and even on this blog. ULC don't require a belief in a deity before ordaining you :-)
I do not have @revk as someone else has it, but it is a dormant, never used, twitter account.
Contacting twitter is almost impossible, but someone said they do have a policy on trademarks, and they have a support ticket help page for that and a form.
So, after literally a few minutes on-line, if that, I have paid £170 to the UK Intellectual Property Office to apply for a registered trademark, personally, for blogging, as the text "revk". I see no others when searching, so that stands a good chance or being accepted. I'll know soon.
That then means I can actually defend against other users of "revk" and maybe get the twitter handle. I may not manage it, after all even Donald Trump still has "real" in his handle. If I succeed where he failed I will be well chuffed. More on this story as it happens.