A normal boy discovers he's already dead, kept alive by a girl who fights invisible monsters in a world that stops for everyone but her. Shana doesn't explain the rules, she just appears when it matters, cuts through the chaos, and leaves you wondering if she's saving him or keeping him as a ghost. The romance isn't a subplot bolted onto action; it's the reason he fights to stay human when being dead would be easier.

Yuji Sakai's ordinary high school days end abruptly when he sees people frozen in a strange fire and a doll-like monster attacking them. A crimson-eyed girl in a dark cloak cuts the creature down with a large sword, then tells him grim news: he no longer truly exists. She is a Flame Haze, a warrior who hunts the Guze no Tomogara, invaders from another world who feed on human existence. Yuji is a Torch, a stand-in left behind after the real him was consumed, but a special one called a Mystes that carries a precious item inside. He names the girl Shana, and his struggle at her side begins. Based on the novels by Yashichirou Takahashi, the series mixes supernatural action with comedy, drama and romance.