Boku Wa Isekai De Fuyo Mahou To Shoukan Mahou Wo Tenbin Ni Kakeru (armaell library.net)

One day, in a certain private school with dormitories, the whole school was transported into another world. I, Kaya Kazuhisa, from the 1st Grade of the High School Section, had been bullied for long periods of time. To kill the culprit who had bullied me, I dug a trap, but unexpectedly I killed a monster. From that mo…