A lobster sat in the water, staring out of his tank.
The people walked by, some stopping to look in. The lobster looked back, though they could hardly tell.
Some chatted, others looked disturbed. But some raised a finger, pulled it back, and tapped.
The “tok tok tok” they made reverberated through the water. The lobster’s mind thrummed each time, making him crazy. Several times per day, people did this.
In normal circumstances, it would have been fine. But with this his only interaction with anything, the tapping, and beating on his brain, made the lobster deeply unwell. If any fingers had been able to get in, he would have pinched them clean off in just one little clamp of his claw.
As the people kept tapping, the lobster became more and more crazed. But there was little he could do, until he figured out how to tap back.