Other names:
Kono Yuusha ga Ore TSUEEE Kuse ni Shinchou Sugiru, Kono Yuusha ga Ore TUEEE Kuse ni Shinchou Sugiru, The Hero is Overpowered but Overly Cautious, この勇者が俺TUEEEくせに慎重すぎる
The story begins when the goddess LRista summons a hero to help her hard mode video game-like world. The hero, Seiya, is exceptional in every way, but he is incredibly cautious. He does things like buy three sets of armor (one to wear, a spare, and a spare for the spare) and go full power against weak slimes (just in case). From ANN.