Urahara said that there are racial opposites: Quincies - Shinigami Humans - Hollows
Isshin was made a Human/Shinigami to counteract Masaki being turned into a Quincy/Hollow right? And had that whole "special string" shabang on the go.
So if Ichigo is basically a Human, Shinigami, Quincy, Hollow type thing right. He's like the "perfect" being/experiment. When Hirako and friends, Masaki and Isshin needed to be "stabilized" by Urahara, Ichigo can do it all Naturally because hes basically bred between the things being stabilized.
I know he was not born a shinigami, nor a hollow. But he was more or less born a Human and a Quincy.
To put it all bluntly. Ichigos the only legit being. Am I correct? So when Tenjiro Kirinji said that the Spirit King has taken an interest in Ichigo, does that mean hes interested in his "biological makeup" or his personality or something?