Bayin is a former member of The Bakram Liberation Front who is recruitable only in the Chaos Storyline Path.
"The Magus Bayin. Age 58. A Bakram formerly with the Liberation Front. He once taught at the Mages Academy of the former Kingdom of Valeria. He was banished from Heim for opposing Brantyn, and then joined the Liberation Front. He did not share their values, though, and so he parted ways with them"