ETA: THE WINNER IS Eloise'sInfernalMachinations who guess it correctly, I was thinking of Daleks from Doctor Who!
Her comment has been shared to the MP, go to the comment and start asking her your 20 questions!

OK, here it goes. I'm thinking of something (the better you know me, the faster you will get this).

I'm thinking of something.

Ask yes or no questions.

Winner who guesses correctly gets to start their own and I will share their post on the MP so they can answer their questions, etc etc. (We'll just unshare once we get it started.) Hopefully that will work.

So ask away!