Eireitachi kara Shuugyou wo Uketsuzuketa Saigo no Eiyuu wa, Yagate Saikyou e to Nariagaru

To protect his older brother, the younger brother chose to fight.[Tokyo Mutation]A mysterious vortex suddenly appeared in the skies above Tokyo, from which monsters poured out, causing a major disaster. While it resulted in many casualties, the situation was eventually resolved by awakened individuals who possessed the skills to fight these monsters.Four years have passed since the "Tokyo Mutation." Yu Uchi, who has awakened to an S-rank skill, spends his days conquering dungeons to protect his only family member, his older brother, from the dangers of monsters.One day, while I was exploring a dungeon as usual, I received news that a dungeon had appeared at my brother's school—