Tommo (The End of Time)
From Tardis Wiki, the free Doctor Who reference
Tommo was a homeless man who lived in the wastelands of London in the 21st century, he was friends with an unnamed teenager. During Christmas time, they encounter another homeless man who resembled a previous Prime Minister, it was revealed that he was actually the Master. The Master killed both him and the Teenager for their life force. (DW: The End of Time)
