User blog comment:Ghmorello/Chapter 859: The Picture Of Mother Caramel/@comment-53507-20170315110545/@comment-5398287-20170315130435

Almost quickly? Caesar can remove oxygen from the area surrounding him, sure, but it's nowhere near an instant kill - people can just hold their breath, you know. And if Big Mom can use Conqueror's Haki, she can sure as hell use Armament Haki to grab Caesar and rip him in half, or whatever, to end the effects.