Mc an old dude, so mc was defending at the border with hero party i think? there was monster(demon not sure) hordes.. they were pushed back. to save his companion Mc decisively stayed there as he got the advantage with his new skill sucking mana(also lifespan i think) mc defended the border for 10 years he fought non stop. No more monsters after that 10 years he went back to the city were there was a statue of him but he got younger in his teen.