PHILADELPHIA--(BUSINESS WIRE)--The top 20 TV series on Xfinity On Demand for the week of April 20 – April 26 were: 1. Game of Thrones, HBO2. Grey’s Anatomy, ABC3. Scandal, ABC4. The Blacklist, NBC5. The Big Bang Theory, CBS6. Teen Mom OG, MTV7. Modern Family, ABC8. The Last Man on Earth, FOX9. Love & Hip Hop Atlanta (season premiere), VH110. Secrets and Lies, ABC11. The Flash, CW12. Keeping up with the Kardashians, E!13. Blue Bloods, CBS14. Scorpion, CBS15. Vikings, History16. The Royals, E