Let This Grieving Soul Retire, Vol. 1 (manga)

'All we need is one goal-to be the strongest heroes in the world!' In a land where treasure hunters scour vaults appearing from the past, Krai Andrey and his friends swore a childhood oath to become the mightiest heroes of all. There's just one problem: While his old companions have become living legends, Krai is the poster child for mediocrity...and he knows it! But despite his best efforts to leave the treasure-hunting life, he has gained quite the reputation by association-and with it, enormous expectations. Can Krai pursue his dream of retirement, or is he destined to fail forever upwards?