Neo Arcadia - Yami ni Saku Niji
ネオアルカディア ～闇に咲く虹～
A land once consumed by darkness is chosen by the King of Light, who sends his son, Rain of the Rainbow, to oppose the ruler of darkness, Ebb. Instead of fulfilling his mission, Rain and Ebb grow fond of each other and choose to live together in the dark kingdom. However, Rain vanishes without explanation, leaving the future uncertain.