Board Thread:General Discussion/@comment-25586591-20141101031745/@comment-6904925-20160421183112

Well it hasn't been confirmed on what his "K" stands for, in fact we don't know what the "BG" stands for. Plus since he is called "BG9", that means their was a BG1 to a BG8, I hope Yhwach used Cang Du body and fused him together with BG9, to make a brand new BG10.