Dennosuke Uchimura is just an ordinary Japanese salaryman, until he's sent to work in Vietnam where he dies in a hit-and-run accident. Uchimura is reincarnated and summoned to another world by the Demon King, who offers him a new job–as one of the Four Heavenly Kings of his army! Uchimura is faced with an offer he can't refuse, but can he do the job?