Torvak was a male Klingon and a member of Klahb who participated in the attempted takeover of the Federation Embassy on Qo'noS. His job was to control the main computer and the security system from the subbasement in the embassy. He liked to listen to Klingon opera and was possibly doing so when he didn't check in over the com frequency. Rov and B'Eko went to find him and B'Eko was left to protect him from Worf who was loose in the embassy.
Eventually, Worf was able to get to the subbasement and reactivate the security system, flooding the building with anesthizine gas. It is unclear what the fates of Torvak and B'Eko were. (TNG novel: A Time for War, A Time for Peace)