Dude this isn’t hard. It’s your assignment, and I’m not taking points here or saying random things, but this is the equivalent of cheating. All they’re asking is for you to be creative and finish the story. They don’t want to see what a random person in the internet knows, they want to see what YOU know. You can do it, just put your head to it and be creative :D
You start to panic, wondering if you will turn into a ghost and run to your bathroom mirror your hand. You can't see it anymore but, you still can... As you wonder what is happening you start to notice that your bed is fading and so are you. Is the Earth fading away you wonder? Luckily, your mom left the TV open and you see that there is a disease that makes you fade and everything you touch. Oh, no you start to think and realize that your very best friend was starting to look transparent yesterday, you touched him at lunch. You now see that your right arm turned a ghostly white and that is spreading to your body. What will you do you ask yourself and you hear that there is only one cure and it is all the way downtown. You can't drive and you can't hold on to your bike so, you will have to walk but before your legs start to fade. You find the shop that sells it that was all the way downtown. It was almost your turn when they came down to one last bottle all hope was up. Then, boom someone exploded the bottle and you start crying and realize that you can now touch your face and sigh with relief so, does everyone else and see that it cured everything in the town. The next morning your alarm clock jolts you awake you reach out to stop it and see that it happens again and rush right back to the store, just to see that everyone else was thinking the same thing...