My aching eyeballs after practicing FCAW.
I once met a guy....he told me he had been in a work-related accident and they thought for a while they would have to remove most of his tongue. I told him, "That would be terrible..."
He agreed, and told me without his tongue, he wouldn't even bother having sex anymore.
I said, "Really....??"
"Yep," he said, "What good is having sex if you can't tell all your friends about it!!??"
The point is....your eyes are what enable 95% of your life. Take care of them.