Edmund Thursday
Edmund Thursday was Jonas Thursday's brother and Effie Thursday's husband. (PROSE: The Crimson Horror)
In 1893, he and Effie entered Sweetville to search for the Eleventh Doctor and Clara. He told Effie to call the police if he didn't return in an hour. According to the Doctor, having "come looking for [the Doctor and Clara]", he either fell or was pushed into a vat of the red leech poison and he turned crimson himself. He ran into the room the Doctor was kept in before falling over and dying from the poison. Due to the effects of the poison, an optogram of the Doctor appeared in his eyes at the point of his death. (TV: The Crimson Horror)