Shitennou Saijaku datta Ore. Tensei Shita node Heion na Seikatsu wo Nozomu

Lord Ranga had risen from a lowly goblin to become one of the Four Heavenly Kings of the demon realm through his efforts, but he was despised by the other Heavenly Kings as the “weakest of the Four." On the day when the human adventurers attacked the demon realm, Ranga was betrayed and lost his life in a conspiracy. Ranga is reborn as a human, but with the memories of his previous life still intact, and tries to lead a peaceful life unlike that of his war-torn past. However, he is confronted by Amira, his former confidant, as well as the enemy who wronged him... Will his wish for peace come true...? (Source: Bunkasha, translated)