Hyakunen Kesshou Mokuroku

Hyakunen Kesshou Mokuroku summary:

Bent, who gathers minerals as a sample for his research, goes to the Akkrum mines which has been closed for a long time. Then, he saw a young person inside it who suddenly collapsed. The boy’s name was Iris. Using minerals as his food, the color of the boy’s pupil glistens with rainbow colors…