Human Doctor/Doctor Who AU (Heart?) ~ David Tennant x2

An alternate version of Season 4, where Doctor Duplicate travels with Doctor. Human Doctor had a hard time dealing with his mortality. Text in vid: Here, let me check. Let’s find out. You and me. I have only one heart. I have only one life. I will die and never regenerate... A friend, I swear... I DO NOT OWN ANYTHING. NO MONEY MADE. MADE ONLY FOR FUN.