Rogue Trader: Totally NOT Space Piracy
Just be thankful you haven't seen his unbound form...
Doscimael is a daemon in the service of Tzeentch. Currently inhabiting the Purity of Insanity (now the Fury), he made a deal giving the group nominal control of the battlecruiser in exchange for the destruction of a certain book from the cargo hold. He offered one way of destroying the book, submerge it in a holy fountain on a shrine world founded thousands of years ago in the Koronus Expanse. The group has since been able to renegotiate its fate to be given to a certain sect of Eldar at the request of Meseri. Doscimael didn’t seem to care either way, but seemed insistent that it get as far away from human hands as possible.
He also seemed to know Nixios as well, which doesn’t bode well for the ruler of Footfall.