Kubinashi Seirei-sama ni Kuchizuke wo

A deadly curse is slowly killing Theo, and none of the healers or magic users he's ever met have been able to help him - until one day, during his travels, he finds the natural spirit Aluvahani.Aluvahani hates humans and has secrets of his own, not the least of which is that he has lost a considerable part of his powers. Theo has something he wants, and so he binds him with a contract to save himself, promising Theo to break his curse at the end of it, as a reward.But will the two be able to save each other? It might be much harder than either of them thought...