Ring of the Dragon SciFi Romance with an Immortal King and a Bad Breakup

For millennia, they fight side by side. Now one king faces a lonely quest. As Light and Shadow, King Pietas and General Cyken share every battle, as well as a fierce and passionate love. But, torn apart by the king's rage, Cyken ends their stormy relationship. When General Cyken falls in love with another man, Pietas undertakes a perilous quest on the dangerous world of Felidae to prove he is the better choice for Cyken. If he succeeds in his quest, it will either bring Cyken back, or drive him even closer to his new love. Pietas must try, for he cannot walk into eternity alone.