system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What are "eye boogers" and how are they formed?
gpt
Your eyes discharge a mucus which contains blood cells, water, skin cells, snot, dust, and so on. While you're awake, you tend to blink and wipe it away regularly. When you're asleep, this removal process is slowed, and the water has a chance to evaporate, letting the dried out remainder accumulate around your eye. It's called rheum.