That made me a little queasy. It looks like attack of the rectum monster. Seriously though it looks like a ball of tubifex worms. http://en.microcosmaquariumexplorer.com/wiki/Tubifex_Worm
Not sure that's accurate. It looks like a solid mass. No individuals proding out any where. They almost look like... alien wall nipples. Putting tin foil on my head just in case those aliens come up out of the toilet to eat my brains.