Shinchou Yuusha: Kono Yuusha ga Ore Tueee Kuse ni Shinchou Sugiru

Ristarte, a novice Goddess of Healing, is tasked with summoning a hero to save the world of Gaeabrande from a Demon Lord. She picks Seiya Ryūgūin, a Japanese hero who has unusually high stats. She immediately summons him and while he appears to be ideal for the situation, she soon realizes that she forgot to check to see what Seiya's personality was before picking him, which states that he is "impossibly cautious". After seeking advice from fellow goddess Ariadoa, Ristarte decides to leave Seiya alone to train. A week later, he manages to reach level 15 doing only basic exercises. When they finally travel to Gaeabrande, Seiya tries to buy multiple sets of armor and other items. Outside of town, the first monster they encounter is a basic slime which Seiya defeats, though he goes overboard, burning the entire area with explosions just in case any fragments are still alive. Just then, they are approached by Chaos Machina, a level 66 demon who is one of the Four Heavenly Kings. She reveals that she was sent out to scout the area in order to kill Seiya before he can pose a threat.