Saya is a vampire commissioned to execute demons. She's pretty awesome at her job too. Slicing and dicing away with a samurai sword making demon sushi. She is sent on a mission to a military base school to sniff out a couple of demons posing as students. When said demonic students start messing with Alice, a human girl, Saya comes to her rescue. Alice ends up in it up to her eyeballs when a particularly nasty winged demon captures her. Saya must get to the bottom of things, rescue the girl and kill the demon master.