Quote Originally Posted by Tzardok View Post
Someone who is inside a creature's stomach has total cover against attacks from outside. He can't be targetted, and emanations or bursts can't get through to him. Now some emanations have descriptions according to which they can pierce barriers (detect evil, for example, is called out as being able to go through stone unless it is too thick, but not through lead), but antimagic field is not called out as working that way.

Because creatures and objects are different things by the rules. If you need an explanation, blame it on souls/animi/other animating forces. And it's not about "someone". It's about "some creature".
Let us suppose that a small lizard has been polymorphed into an allosaur. While in that form, it swallows a person whole. Then it is targeted with an AMF. Is the small lizard ripped apart? Does that depend on whether the person has yet died? Or if the person is actually a polymorphed butterfly?