This is the Catpanion Cube, a feline residence made by Instructables member/Aperture Science vet/
cat slave Rachael Whitaker. I hear that when you place your cat inside, she’ll be simultaneously dead and alive, stuck inside the dimension that the Portal gun uses to generate shortcuts. When you place your dog inside, he’ll just poop in it.
Rachael made the Catpanion Cube out of foam padding and some fabric. She held the Cube’s walls together using pins and thread. The Cube doesn’t sing though.
Open a portal to Instructables to find out how to make your own Catpanion Cube. Your cat will know that you’ll incinerate her in her sleep if she ever misbehaves.