From the anime: My Instant Death Ability Is So Overpowered, No One in This Other World Stands a Chance Against Me!

While heading to a school field trip, the school bus is summoned to another world by a Sage who shows just how horrible she and this world is by killing the adults for petty reasons and telling the students they are to be trained as sages to fight demons and complete missions. She only takes the gifted ones, leaving the rest (including you, that was sleeping deeply, and your classmate Tomochika Dannora) to die. With no choice but to continue, you and Tomochika search for a way back to their own world, but your unnatural calm apathy towards the oddity unnerves Tomochika. In truth, your not an ordinary kid...you can kill anything or anyone you wish just by willing it.