Wait… Natsu can open it? The 9 demon gates of Tartaros were trying so hard to open the book and Natsu could open it? I mean he is END and everything but I never noticed the hint.
Since igneel was the king of fire dragons who was trying to destroy END and lived for hundreds of years he knows what’s going. I don’t know if it was just foreshadowing Natsu as END but… it means something!!
Igneel obviously knows it’s sealed, so he wouldn’t tell him not to open it if he couldn’t, right? If you look into this, Igneel is literally saying Natsu is able to open that book, since he is END