"...W-w-what should I do? I'm being transported to a hellish battlefield!"As humanity is on the brink of extinction in the war against the demonic beasts, the maid girl Orsera inadvertently teleports to a forest on the front line of the battlefield.With no weapons or combat experience, all she has is a useless unique magic that "summons things that humans no longer need."When she encounters a large dragon demonic beast and finds herself in dire straits, she takes a gamble and summons a magical weapon called a revolver, and a heroic, battle-crazed girl!?Her useless unique magic is actually better suited to fighting than any other magic...Before she knew it, she had become the last stronghold to protect humanity!?The weakest maid carves out the future for humanity!The end of the world, a survival fantasy of rising to power begins!