Book of portraiture

The Book of Portraiture has no use other than the one involved in Zogre Flesh Eaters quest, where it provides a hint to the player. It is found, along with charcoal and a piece of papyrus, in the drawers in the room of Sithik Ints. When read, it says, "All interested artisans should really consider taking up the hobby of portraiture. To do so, one uses a piece of papyrus on the intended subject to initiate a likeness drawing activity." By following the book's directions with the piece of papyrus and charcoal (but not necessarily the book) in the player's inventory, and while in Sithik's room, the player produces a "Sithik portrait".