Salaryman ga Isekai ni Ittara Shitennou ni Natta Hanashi / サラリーマンが異世界に行ったら四天王になった話

Suffering years of workplace abuse and shuffling between different countries to take on jobs no one else wants, Dennosuke Uchimura never expected his next transfer to be to another world. After all, his tireless efforts catch the Demon Lord's attention; he deems Uchimura the perfect candidate to fill the vacant spot among the Four Heavenly Generals. Despite Uchimura being an ordinary human, he earns the Demon Lord's recognition through his knack for solving impossible situations—a skill he honed through years as an overseas manager. With rising dissension among the demon army and failing negotiations with other tribes, it is up to Uchimura to justify the faith bestowed upon him and bring one final push for the Demon Lord's vision of dominance and perfection. ...