Axis Mundi Reaper: Obelisk Slayer.

Deep within the reach of the Obelisk Church, a powerful theocracy governing the globe, sixteen-year-old Kiyoshi Mortis lives a dangerous double life. Known to the world as the "Obelisk Reaper", Kiyoshi has spent years traveling between nations to systematically destroy the Church's religious and militaristic landmarks. His crusade is fueled by a dark partnership with Darius, a high-ranking fallen angel whose soul is bound to Kiyoshi's own. Together, they have arrived at the holy capital of Magenta Falls to target the Grand Obelisk—a massive structure rumored to power the world and reach into the heavens. To gather intel, Kiyoshi enrolls in the prestigious Magenta Falls Academy, an institution for supernaturally gifted students. However, staying undercover is easier said than done when a celestial supercomputer labels him "sinfully corrupt", sending the student body into a fanatical frenzy.