:In a realm where angels and demons exist along with other fantastical creatures, an unexpected love story between two beings with opposite rules and beliefs from opposing sides of the cosmic spectrum start to emerge... :Just like any other cliché story Sai, despite his reputation of being a son of a God, is actually quite rebellious and has acquired the name of "The dark angel", meanwhile in the other side of the spectrum a demon prince lies In the depths of the demon realm, boy named Xian,Which is secretly quite soft and loving despite his parents being the demon king and queen...