Kanchigai no Atelier Meister: Eiyuu Party no Moto Zatsuyougakari ga, Jitsu wa Sentou Igai ga SSS Rank Datta to Iu Yoku Aru Hanashi / 勘違いの工房主～英雄パーティの元雑用係が、実は戦闘以外がSSSランクだったというよくある話

Despite having no real combat talent, kind 15-year-old Kurt Rockhans belongs to the famous party Flaming Dragon Fang. He is perfectly satisfied as the party's helper—until the other members kick him out and replace him with a stronger ally. Left without a way to provide for himself, Kurt begins searching for a job. With his job prospects limited by his lack of combat ability, Kurt gladly accepts any work that comes his way. During one such job, he meets Yulishia, an adventurer formerly employed by the royal family. Surprised by Kurt's impressive work, Yulishia discovers that he is no ordinary boy: Kurt possesses an astonishingly high aptitude in a variety of non-combat fields. Due to these talents, a court official tells Yulishia to offer Kurt a high status in the kingdom that would allow him to live in peace for the rest of his life. When Yulishia informs Kurt about his potential rank, he brushes off the offer, refusing to think of himself as above other people. Still unaware of his real power, Kurt continues taking as many odd jobs as possible, which might just make him a pivotal part of the kingdom before he even notices it. ...