system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why does our skin take on the texture or impression of whatever we sleep on, instead of staying elastic and returning to its normal state immediately?
gpt
Laying on something long enough to leave a dent causes the fluids in the tissues to be squished into surrounding areas instead. It takes some time for those fluids to find their way back to where they belong.