Goblin Slayer Side Story: Year One, Vol. 3 (manga) — Kumo Kagyu

The novice warrior, who took part in the subjugation attack against Rock Eater, throws himself in the midst of rigorous fighting to honor his fallen comrades. Meanwhile, a young boy single-handedly fights to protect a small village from the threat of goblins. But while felling goblin after goblin in the pouring rain, he's faced with a danger that comes crashing in with the thunder and lightning...