Shinmai Ossan Boukensha, Saikyou Party ni Shinu hodo Kitaerarete Muteki ni Naru.

The Ossan Newbie Adventurer, Trained to Death by the Most Powerful Party, Became Invincible

新米オッサン冒険者、最強パーティに死ぬほど鍛えられて無敵になる。

The Rookie Middle-Aged Adventurer Was Trained to Death by the Most Powerful Party to Become Invincible