What is outside our universe and after that and after that? universe?

Lol, I think I got the message after the first paragraph :) There are thousand more universes outside our universe, but that's all we know so far. I don't imagine that we are "inside" a bigger universe, but part of a group with many others, but I suppose that's out for debate. But I do know it is never ending, and some people could go mad trying to think about it. It is difficult to imagine a never ending because humans think in linear terms. Hope that helps you.