Howl's Moving Castle meets Pacific Rim
Diluv is used to the dying village he lives in, the way there's quakes that rattle the walls when it coughs and the way it lists a different way every day. But in order to survive, they must join a larger city and leave their village behind.
Assigned to the conjoined corps that defend the city against the gargantuan beasts, Diluv must discover just what it takes to conjoin with a stranger for the sake of the fight, and secretly try to save even one small piece of his village before it's gone forever.