User blog comment:Xilinoc/Ch. 668 - BIGGER,FASTER,STRONGER/@comment-957629-20160331154647/@comment-11446176-20160403125230

The way I see it (at least) is that she had a short life before, as an Asauchi, which he then picked up, chipped a hell of a lot, probably needed to replace the handle/guard etc etc which led to physical changes to the sword itself. Based that weird fight Ichi had with the Asauchi back in Houou-Den, the asauchi had their own generic spirits, which were then imprinted on by Ichi.

Whos to say that the spirits had their own memories from before, from the time they were held by a lower class soldier, before being "imprinted" by Zaraki?