Answer:
What is black when you buy it, red when you use it, and gray when you throw it away?
I am as hard as metal, yet as flimsy as glass. I shine like a star, yet I am only a rock. What am I?
I am not a toy though many use me for pleasure. I have a butt but I cannot poo.
I belong to everyone. Sometimes make you happy sometimes make you sad. I will never end until the day you do.
What has feet and legs, and nothing else?
The warmer I am the fresher I am.