User blog comment:FTonlyAssassin/END & Natsu Theory/@comment-80.216.5.82-20151130163431

my theory was

Natsu and END are the same yet diffrent, split personalities you cold say Igneel foght END and he was winning but to save himself END split himself into Two Pieces the Human and the Demon half that became a book.

that would work, of course then how old was the child? my theory would then be that END had sealed that half into some crystal to stop its aging utnil it was hatched 400 years later. and when Igneel having watched that shell for a long time took pity on the boy and got to love him as a son.

meanwhile the Book and the Demon ended up with Tartaros. but Mard Greer decided many years later to use a diffrent method to awakenen END. seein that END was made of a Human shell disgusted Mard Greer so he thought by removing all Magic the Book of END would still revive, this time as a real Demon.

all this is however not so likely. but I do belive they are seprate and not just an amnesia. the real question that will answer all is if the Book of END is just a Phony and a Decoy or the real deal. and also on how long have Igneel watched over Natsu?