User blog comment:Kaido King of the Beasts/Chapter 884: Sing or Swim/@comment-31429799-20171103140934/@comment-24850639-20171106180011

I honestly don't think there is any questioning that he can transform his body into the substance. Trebol was able to be "cut" because it was by the Ope Ope No Mi, it wasn't his body literally being cut in half. Katakuri has displayed on multiple occasions now that he can turn his body into mochi, and then trap his fist in said mochi. Trebol had a physical body underneath a huge coating of slime, which is what he was actually moving out of the way. Katakuri is not wearing some outer coat of mochi, which a weaker body underneath. That is his actual body that he is shapeshifting in such a manner. So him catching Luffy's fist in his forearm....that wouldn't have been possible if he wasn't literally becoming mochi. Him trapping Luffy's G4 fist in his torso this most recent chapter.....that wouldn't have been possible if his wasn't transforming into mochi.

Him transforming thanks to busoshoku doesn't really seem to make much sense when the very nature of busoshoku is hardening/fortifying something in the form that it has already taken. Yes we've seen admirals and Rayleigh use it to form something of an invisible shield before, but never to shapeshift something. Katakuri displaying this ability certainly presents logia-like qualities, and I have to agree with SJW on that assessment.