User blog comment:Mangetsu20/Four Battlefronts...not a Star Wars reference (FT - 462)/@comment-3045936-20151121225522

Something I just wondered. Brickslow's Figure Eyes can see souls right? Than why hasn't he ever seen that Natsu is an Etherious? Only theories are these two I have.

1. As he wasn't created like the other ones, is where he still might be (human) while an Etherious.

2. The Book of END: contains the technique that revived him. So when it opens it will turn him back into END but until then he is human.

This last chapter made me realize this.