Flesh Piles are piles of flesh left over from other students. They can be found in any level.
You can press E to pull out some flesh, with a random chance of some artifact called "Viktor's Flesh."
You can scare Cleany away by leading him with trash over to the pile of flesh.
You can anger Laura and Mix by running into the pile of flesh.
With the artifact, you can cover yourself in flesh, and play dead. After 10 seconds, it will ware off. This has a 25 second delay.
With the artifact, you can lead Mix to whatever area you want, since he likes to eat human flesh.