Kevin Hunter

Kevin Hunter is a character in the Sherlock fan-fiction, Madison Hunter. He is the father of the series' titular protagonist and two other children.

Biography
Kevin Hunter has twin children with an American woman named Arabella, who is a secret CIA agent and secretly married to Kevin. Later, he and his wife have a third child named Madison. He keeps his children's mother's identity a secret. ("A Study in Pink", "The Final Problem")

According to Sherlock, Kevin dated many women and is now deceased, and Maddie later confirms that both are true, but she implies that he also dated men too despite the fact Kevin and Arabella were married, shocking Sherlock completely unawares. ("A Study in Pink", "A Scandal in Belgravia"