A Simple Life with My Unobtrusive Sister

Ten years ago, a mysterious giant labyrinth suddenly appeared on the surface of the world. Adventurers from across the land flocked to its depths, chasing fame and fortune. But for you, the labyrinth called the Abyss is not an adventure — it is your only hope. Your beloved sister Mio suffers from a rare illness no doctor can cure. The only clue to saving her lies somewhere in the dark below. Every day, you descend alone while she waits patiently at home. The Abyss only grows more dangerous. Will you find the cure before it is too late?