SigOpram said:
Plothole? Zaraki met Yachiru way BEFORE he became a shinigami. How come she's a zanpaktou? Not only that, she also has her own zanpaktou.
Remember Zangetsu (the Quincy Spirit) can create his own sword and Ichigo was deceived thinking that his sword was his real zanpaktou without realizing that it needs to have an asauchi made by Ōetsu Nimaiya. So technically, her sword maybe created by her power.
Also, even before they got an actual asauchi, the sword spirits may manifest in them just like in Hitsugaya's case.