User blog comment:B214/Chapter 499: Gray & Juvia/@comment-122.162.151.217-20160829110028/@comment-29693708-20160829181414

if neinheart is an enchantment I expect he will be an object of emotional significance to both erza and Irene, not a sword; an object erza will recognise and wonder how it came to be in alvarez's possession. this would fit quite well with neinheart's 'memory' theme and could give us some more erza backstory.