Mineko to Maou ~Isekai Teni no Wakagaeri Saikyou Baasan, Saijaku Maou to Yonaoshi Suru~

Demon Lord Maurishutra faced a life-or-death crisis after his throne was stolen by a coup and his life was targeted. Using forbidden magic passed down by the royal family, he summoned a loyal knight from another world, but the one who appeared was 80-year-old grandmother Mineko, who was on her way to a maple-viewing bus tour—?!