Seisan Mahoushi no Rakuraku Henkyou Kaitaku: Saikyou no Ajin-tachi to White Kokka wo Kizukimasu!

Joshua is an overworked, underpaid production mage for the prestigious Knights of Schwarz order. When the order’s corrupted commander dismisses Joshua from his toxic job, he embarks on a quest for a new purpose. Along the way, Joshua's path intertwines with Illya, the princess of a Demon tribe, whom he saves from hunters targeting “demi-humans.” As thanks, he’s welcomed to the Demon tribe village. Witnessing their torment by the Demon King's army and slave traders, Joshua resolves to employ his production magic to aid them. Get ready for a fantasy where the greatest production mage and his friends work together to craft a splendid nation! (Source: Manga UP!)