The League of Gentlemen star played chief vampire Mr Snow in the final episodes of the BBC programme's fourth series last month.
Recalling his experience on set, Gatiss told Radio Times: "I said to the director, 'I have to say I think I have waited all my life to play this part'. I felt like I had come home. I don't think I have ever had so much fun in my life."
The Sherlock writer also spoke of his ambition to appear on a show that is worlds apart from Being Human.
"America's Next Top Model - I am obsessed with it," he revealed. "The next cycle is called 'The British Invasion'. I don't know what they are doing but I want to be a guest judge on it."
Being Human actor Michael Socha, who plays werewolf Tom, recently named Gatiss as one of his favourite guest stars.
"He really, actually, genuinely scared me when I was doing scenes with him," he said. "He's incredible."
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