You can use whatever story you want. You should play more games, watch more movies, read Dr. Seuss books, basically do whatever you can to get fragments of story elements you want to use so you can make your own. You can't seriously believe some random people are just going to write you a story. If they did then maybe they'd use it for their own games.
I'm going to suggest something stupid like you character isn't carrying 2 boxes with him but 2 "balls".
If your character is carrying 2 "balls" he can't jump. If your character is carrying no balls, he gets scared by random enemies so you lose control and let the ai take over for a short period of time.
He's dragging his "balls" all the way to the finish line...