Dragon? Demon? Both?

Both

(inside Natsu's body, where the 2 seeds are merging)
    Two seeds could be seen merging, as they finish, instead of killing Natsu like everyone expected, the seeds became something more, a Dragon demon seed, this seed turns a human into a, well, Dragon demon, a being that hasn't been seen in millenia.
(back in Natsu's mind)
    "H-How is this possible!?" Igneel exclaimed in shock and confusion. I was feeling dragon-like features appear on me; My forearms were covered in crimson dragon scales, my hands turned into claws, also, my feet and lower leg changed the same way as my hands and forearms did. My face was like during my Dragon Force, however, the scales felt more permanent, the top of my head had sprouted two horns; my back didn't change much, except for the pair of dragon-like wings and tail; black fire tattoos also appeared across my body where there wasn't any scales. Once I calmed down, I looked at himself, "What happened to me!?" I questioned.
    "It seems that you didn't die from the seeds merging, in fact, the exact opposite happened, you became stronger" Igneel answered with a smile. "It's about time for you to return to your friends, they are worrying a bit too much right now."
    "Ok Dad! See ya later!" I replied cheerfully as Igneel disappeared.