"No matter how far you go, you'll never be anything more than an errand boy!"

Fool, an F-rank adventurer who could use only Heal, a single-target recovery spell, was looked down upon as the guild's errand boy and lived an unfortunate life. Fool was at a loss, but his encounter with Cecilia, a beastkin girl, would drastically change his fate—!? Making full use of his infinite mana, Fool rises from the bottom to become a first-rate healer alongside his trusted companions!