Shakugan no Shana Movie

Wielding a blazing sword, Shana's sole purpose is to fight demon-like beings that consume human lives. During a volatile war to stop a foe from devouring every life in Misaki City, Shana cuts Yuji in her crossfire. When the villain discovers this teenage boy is gifted with an immense power, he holds Yuji hostage to lure Shana into a trap that could to destroy the huntress and the entire city! (Source: FUNimation)