Kaul Hilo is the second-born son of Kaul Dushuron, and brother to Kaul Lanshiwan and Kaul Shaelinsan. At the start of Jade City, he is the Horn of the No Peak Clan. At 28, he is one of the youngest people in history to become Horn.
Kaul Hilo was born into the most prominent family of the No Peak clan. He was a student at the Kaul Dushuron Academy, and graduated sixth of his class, primarily due to a series of misdemeanours which affected his final mark. Naturally charismatic, Hilo was highly regarded among his classmates, many of whom served him later on in life as his Fist and Fingers.
Hilo assumed the position as Horn of the No Peak Clan a few years after graduation, and excelled in the role. His right hand men are Academy classmates Maik Kehn and Maik Tar. As of the beginning of Jade City, Hilo is romantically involved with their sister, Maik Wen.
In his role as the Horn of No Peak, Hilo maintained the clan's control of various areas in Janloon by direct and covert battles against their largest rival clan, The Mountain. Due to his effectiveness as the Horn, he was subsequently targeted for assassination by the leadership within The Mountain clan.
As a green bone warrior, Hilo has the natural affinity to jade and is able to wield it to enhance his combat abilities. Hilo is regarded by many characters as a lethal and highly competent warrior, with naturally high jade tolerance.
He is also a 'natural Horn', with an innate magnetism that galvanises his men to fight for him and the clan. Lan feared that many of the Fists and Fingers of No Peak were truly only loyal to Hilo, and not the clan itself.