100 word challenge, week 3

The prompt for this week is 5 words. They can be used anywhere, in any order. they are:
                              ...Gateway, cold, running, black, friend...
Here it is...

Kate got up and went to the window. Something caught her eye. A black figure was walking into the darkness. She froze.
"What's wrong?" asked her friend Melissa.
She pointed to it. The girls darted outside.They shivered. It was cold.
"There!"
The figure was slinking out the gateway. Kate started walking. She could just make out a box.
The box had legs and it was running! How scary!
Kate screamed.
"Let's go inside!"

The next morning they related their adventures.
"It was me." said Kate's brother "I took my go kart down the hills. Those legs were the wheels."
The girls just looked at each other and sighed .
............