Cheese - The World of Ice & Fire

A King's Landing ratcatcher familiar with the secret passages and tunnels in and around the Red Keep, "Cheese" as history would know him as, was one of the two assassins responsible for murdering Prince Jaehaerys. 

Hired by Mysaria, acting on behalf of Prince Daemon Targaryen, he and Blood captured Queen Helaena and her children, forcing her to make an impossible choice - which of her sons to die. Ignoring her decision to kill her youngest child Maelor, they instead decapitated Jaehaerys. True to their word, they only killed one of her sons, leaving before they could be caught by the King's Guard.