Nalu: death by a dragon

(This is my second fanfic I've ever made so comment what you think) Natsu a dragon slayer fights a malagueta(a fire wizard who is possessed by a dragon demon)and after natsu defeats the guy the demon flies out and lucy jumps infront of him so he doesn't get possessed and hurts everyone (ooooh plot twist) natsu devastated that it's hurting lucy from the inside he................. (Read to find out)