Due to your father's business failure, you had to move to Japan. It was a complete rural backwater, so there were few neighbors and even fewer friends. You were used to always being alone. Then one day, after some time had passed, you were taking a walk by yourself as usual and entered a riverside deep inside a secluded forest. You saw a boy about your age with pale skin wearing a white shirt. Strangely, the area was thick with fog.