Vyrewatch guard are Vyrewatch found in the upper and middle tier of Darkmeyer, guarding the jail cells in the respective tiers.
In the middle tier, the guard is guarding the cell containing Maria Gadderanks. He can be locked inside the adjoining cage in order to take off the disguise and free Maria by breaking the jail door lock.
In the upper tier, two guards are guarding a cell containing a number of Captured Meiyerditch citizens. The guards will want you to kill a number of these citizens in order to prove your worth as a vyre - you will gain status for doing so. If you choose not to kill the citizens, one of the guards will send you on a hunt for his stolen Darkmeyer notes to buy bottles of blood from the Darkmeyer blood trader. The player must travel to the lower tier and threaten a Canifis settler with a wolfbane dagger to retrieve the notes. Afterwards, the player must speak with the Darkmeyer blood trader and select the two types of bottles of blood the guard asked for. Doing this task will gain less status than killing the citizens.