Queen Juana I of Castile had an odd attachment to her dead husband's corpse.
Caligula from Julio-Claudian dynasty had a close relationship with his horse. He even used to have dinner with the horse.
Ivan IV of Russia was better known as “the Terrible” as he used to torture people and animals.
Louis XIV received many enemas throughout his life.
Christian VII was the king of Denmark and was known to be a chronic masturbator.
Princess of Bavaria, Alexandra Amalie had an OCD and refused to wear any color that wasn't white.
Napoleon hated to lose at cards, chess or any other game, and took pains to avoid doing so.
King Ludwig II Of Bavaria loved spending his time planning how to build castles.