It was said that a Hollow killed with a Zanpakuto is cleansed of all of his post-mortem sins, and is sent to soul society (unless he had committed sins in his lifetime, then he goes to Hell).
What would then when a Menos, which easily contains hundreds if not thousands of souls, is killed with a Zanpakuto?
Would all of the souls be released? Or perhaps the souls fused into one? If so, does that mean that Ulqiorra is somewhere in Soul Society right now?
Is such a thing explained anywhere?