User blog comment:B214/Chapter 503: The Last Sight Seen/@comment-5303512-20160926122648/@comment-1359322-20160926132732

What changed? Did he kill Dimaria? Did he lose recognizance of his friends? He clearly still has his sanity, you're just jumping to conclusion now like in Mavis' case. Until you seen an actual change, you shouldn't assume there is any change.

Besides your logic is slightly flawed, the first generation Dragon Slayers all undergo changes when they enter Dragon Force, by your logic it means that Natsu, Wendy and Gajeel are transforming into something else because they underwent transformation in Dragon Force which clearly isn't true at all.

You can say i'm being stubborn but until i actually see Natsu really stop being Natsu completely in personality, mentality etc, i don't see Natsu's demon power awakening being anything different from Natsu obtaining power-ups like Dragon Force, Lightning Flame mode or even the Fire Dragon King mode.