In this world, when humans reach seventeen years old they are bonded with immortal beings who wield special powers and are required to follow certain rules. Some people view this bonding as a blessing, while others see it as a curse.
If these rules are broken, humans risk losing their mortality, becoming trapped between worlds, or facing a fate worse than death, and this is known as 'The Shadowbind'.
Asher Flynn receives his Sagea during the Bonding Ceremony and this happens two years before schedule.
However, because of the 'rules' that cannot be broken after the ritual, Asher accepts his Sagea with a heavy heart.
The unexpected turn of events makes Asher realize that his so-called 'pathetic Sagea' is the last living heir of the first legendary Sagea master.