He, the son of Severn, is the strongest warrior in the Kingdom of Light. He gained great power due to an accident and attracted the attention of the dark forces; she, the daughter of Severn, the half-sister of Zero, a hybrid of the Blood Clan and the Light Clan, is the 19th generation heir of the Emperor Vosges Castle. There are many secrets and dangers waiting for them in the universe, and how will they face them...