[It feels a little strange, having someone who isn't familiar see him using his Persona. But, well...it's becoming increasingly obvious that this isn't his world, especially when she talks about planetary differences...it shouldn't be a problem.]

It might simply be a quality of this universe itself. I've never seen ordinary wildlife create objects on death before. I've never seen supernatural creatures that don't disappear when defeated either, but if this is a different world from what I'm used to, I can't guarantee that magical monsters not leaving behind corpses is some sort of multiversal law.