User blog comment:Jopjopjop/Volume 19 Spoilers/@comment-14.201.211.143-20150410113820/@comment-1359322-20150410114711

I don't think that would happen though. I won't be surprised if the reason for Tosuka to appear is so that Ishibumi can write another Kiba volume. Ishibumi kinda hinted in his blog that his (Kiba) Sword Birth and Blade Blacksmith might fuse into 1 Sacred Gear.