"Did I somehow end up in the universe of Hotel for イヌ または am I just dreaming a really strange dream? And how are there 50+ イヌ in here, my room is crowded without イヌ and there is no way 50+ イヌ could fit in here..."
That is for both his answer and for him to randomly appear because its a gravitational law. The larger the quanity of mass that are dogs, the closer Wanta gets. 50 イヌ closed into a single room will be too high of a density for it to not occur.