Dark Heresy n' Friends
He's called that because he has long teeth.
Longtoof is an Ork Boss who lives on Tarsus. He is apparently a trader and craftsork who provides weaponry to a battledome run by Rox on Tarsus.
He lives in “Tarsus, ups in the top floors, where it’s nice n sunny n’ the like. He’s proper noble, ’e is.”