Originally posted by: Dezalanel
"Kurumadani's Zanpaku-tou name is Tsuchi-Namazu (sp). It looks like Chakuramu (OP?)
Its call is "Good morning! Tsuchi-Namazu."

Kurumandani is that replacement Shinigami. Oh and about the Skull, he can use it to get out of his body like how the "skull" glove and the "skull" on Uraharas cane. So I do not think the Skull is meant to be bad.
Damn, I missed that reading it way early in the morning.

Still, Isshin totally needs to call his Soul Slayer out like that.

Also, the skull is sinister. Look how weirded out Uryuu is when Ichigo pulls it out, and the "maybe I'm just worrying too much" line - which never indicates good things in a manga.