|"I smell CHEEZ!"|
— The Rat
First appearing in Bowser Junior's Cheeseburger, he was the one stealing the cheese. Despite asking nicely, Chef Pee Pee fails to get the cheese from him. Later, the chef uses a mouse trap, but the rat grabs the cheese without it going off.
In Bowser's Dinner Date, the rat smells the nasty cheese cooked by Chef Pee Pee.
In The Grilled Cheese, the rat repeatedly takes Chef Pee Pee's grilled cheese sandwiches. Because of this, Chef Pee Pee hires the Brooklyn Guy to handle him. The rat simply bites him, so they use more mouse traps, only for the rat to take the cheese, and return the sandwich. The rat later pushes Chef Pee Pee into the traps while he was getting his sandwich. When he returns, he thanks the Brooklyn Guy for the cheese, but gets killed by the Mouse Trap board game, much to the Brooklyn Guy's amusement.
His favorite cheese is "Gouda Cheese."
- Despite being killed in The Grilled Cheese, the Rat reappears in The Call Of Duty Blackout, which was uploaded after The Grilled Cheese.
- It's possible that the rat wasn't actually killed after being hit in The Grilled Cheese, he could have just been knocked unconscious from the hit.
- It is unknown what happened to the Rat after the events of Bowser's House Fire!.
- The Rat has not made an appearance on SML since 'the Call of Duty Blackout'.
- The Rat is portrayed by the Folkmanis White Mouse puppet.
- His puppet was used in a Titottoter video where he was the Antagonist of Jet's Cheesy Problem  and he was called a mouse in that video and didn't speak, meaning it was a completely different character and just uses the same puppet.
Likes and Dislikes
- All kinds of Cheese (likes Gouda best)
- People who don't let him have cheese
- Chef Pee Pee
- Brooklyn Guy
- Lack Of Cheese For Him