User blog comment:Xilinoc/Ch. 542 - THE BLADE IS ME/@comment-3230060-20130619150641/@comment-5398287-20130619153642

He evaporated it. The Zanpakuto assistant said that.

And as for that, um, no. Yhwach's soul isn't in Ichigo, his blood is. There's no long-spanning completion goal behind all of this: Ichigo is just related to Yhwach.