Mortally wounded in battle, the dying king was brought to the temple of Priapus, the god of fertility. His final load would be mixed with the soil to ensure a bountiful harvest. His cock and balls would be carried into the next battle to ensure victory.
Hot fantasy that the seed of the fallen king has regenerative power and fertility beyond his death. I love the focus on the cock and balls as the center of a warrior's power. It explains why the sex meat is not only harvested as trophies by the victorious enemy, or possibly destroyed or consumed, but also why respectfully removing the manhood from a slaughtered leader, and carrying it forth, allows his men to fight with the same loyalty they gave him while he was alive. The seed that a warrior pumps from his dying cock is his final gift to his brothers and to his homeland.