A computer is like a living organism. Its charger is its life support. If you "pull the plug," you are letting it slowly die.
Computer Life Support
Explanation
Explain Bear
Alright listen up, bud. So, like, a computer needs its charger to live, right? It's just like how you need snacks to survive your boring life. Pulling the plug is like taking away its food, and it dies, just like you'll die alone.