User blog comment:Xilinoc/Ch. 651 - The Theatre Suicide SCENE 5/@comment-6073876-20151112112757

so as conclusion, Katen Kyokotsu both are Kyoraku's Zanpakuto...he just calling Kyokotsu to return the blade that she's hiding with her the whole time, which is Ise Family Zanpakuto..i'm feeling relieved it turns out that way, rather that Kyokotsu is just a "borrow" sword from Nanao's mother, which ruin Kyoraku's reputation as one of Shinigami that have dual swords/soul along with Ukitake and the newbie, Ichigo