This may look like some kind of art installation, but it's actually the inside of an inflatable mattress. The strings connecting the top and bottom are there to keep the mattress' shape, or else it would be shaped like a balloon when inflated. Older or cheaper air mattresses are sometimes supported inside by panels made of the same vinyl as the mattress itself, but the string method is better for air flow.
Redditor -who_knows- took this picture through the plug while the mattress was deflating, which explains why the strings are not taught. -via Twisted Sifter