Rogues in the House by Robert E. Howard

At a court festival, Nabonidus, the Red Priest, who was the real ruler of the city, touched Murilo, the young aristocrat, courteously on the arm. Murilo turned to meet the priest's enigmatic gaze, and to wonder at the hidden meaning therein. No words passed between them, but Nabonidus bowed and handed Murilo a small gold cask. The young nobleman, knowing that Nabonidus did nothing without reason, excused himself at the first opportunity and returned hastily to his chamber. There he opened the cask and found within a human ear, which he recognized by a peculiar scar upon it. He broke into a profuse sweat and was no longer in doubt about the meaning in the Red Priest's glance.

But Murilo, for all his scented black curls and foppish apparel was no weakling to bend his neck to the knife without a struggle. He did not know whether Nabonidus was merely playing with him or giving him a chance to go into voluntary exile, but the fact that he was still alive and at liberty proved that he was to be given at least a few hours, probably for meditation. However, he needed no meditation for decision; what he needed was a tool. And Fate furnished that tool, working among the dives and brothels of the squalid quarters even while the young nobleman shivered and pondered in the part of the city occupied by the purple-towered marble and ivory palaces of the aristocracy.