Kirth was a Hedgeknight from the Riverlands in the employment of Lord Wyl during the Dornish civil war. He saved the lord's life and was granted a boon. He asked become a knight in house Wyl's service. Lord Wyl accepted gladly.
Ser Kirth eventually became a knight in the household guard of House Wyl of the Boneway.
He is currently Lord Timeon Wyl's Guard Captain, as well as closest friend.
He is in his late thirties and lowborn from the Riverlands. He is an excellent fighter and loves to frequent brothels.