Look closely next to writer Bryan Cogman’s name in the opening credits and you’ll see his ‘House Sigil’ is a vomiting maester. This is allegedly a vomiting maester after Bryan had a bit too much too drink at a wrap party though I'm not sure how true the claim is. The answer by gives the reasoning for his in that it is a turtle because 'Turtles have always been my sigil, I suppose.'.
