The Hundred Line -Last Defense Academy-

https://store.steampowered.com/app/3014080/The_Hundred_Line_Last_Defense_Academy/

Unravel the Ultimate Battle Against Darkness Step into a world where ordinary life shatters in the face of the extraordinary. In The Hundred Line: Last Defense Academy, Takumi Sumino—a seemingly average teenager—finds his safe, mundane existence upended when grotesque monsters invade his school. Drafted alongside 14 other students into a last-ditch Special Defense Unit, they must band together and fight for survival over 100 intense days, confronting not only relentless foes but also the hidden truths behind their very reality