onozukai no ossan bōkensha ichaerohāremu eiyū tan

Douglas is an adventurer who uses an axe as a weapon, a very serious and hard-working man who has lived an unrewarding life. One day he is betrayed by his teammates in the depths of a dungeon, and almost loses his life. In the midst of his despair, he finds an axe, a fearsome weapon with mythical power. After this great find, his life changes drastically from that day on. He becomes a man loved and adored by three beautiful girls. The forty year old adventurer begins a journey to become a hero to be envied by all.