Sons of eclipse: A hero and a monster

Two twins are born on a stormy night in kingdom of elariya to the duke aldric and duchess elara ."Loir"the older one born 10 minutes earlier is a reincarnated hero from the past who saved the world centuries ago from the soul king who almost wiped 70percent of the population. A prophecy states that hero loir will be born again to save world from doom and bring peace to the world but it does not state anything about the second twin "Luther" . This story follows luther and mystery of his birth as the spirit queen herself descends to bless him when he was born. only their parents know about the potential of luther as the story progresses we see luthers journey to his true self who is he? a friend ? a fellow protector ?? or the doom itself ??.