Ein has been saddled with the job of "Appraiser," the weakest and least fortunate of all the jobs one can be born with, as the only power it grants is the ability to appraise things. Treated cruelly by all and reduced to a litter collector by his peers, Ein has grown to hate himself and lives his days in spineless self-abasement. But when he meets Yuuri, the spirit of the World Tree, and her protector, Ursula the sage, Ein's fate takes a drastic turn. With the gift of a Spirit Eye from Yuuri and the help of Ursula in learning how to use it, Ein grows stronger and stronger, until he's ready to take Yuuri on her long-desired journey to meet her World Tree's sisters. He goes on to overcome all sorts of challenges, armed with his natural kindness and his new-found courage.