Disclaimer: Last I checked my name was not J.K. Rowling.
Author's note (a.k.a. shameless self-promotion): For everyone who read 'Once Upon a Time', the first oneshot in this 'series', I have a drawing up on my deviantart account (link in profile) based on that. I will also be posting a manga version of 'The Frog Prince.' If you haven't read either of those stories, go read them (and the other oneshots in the series) once you finish this one. Or read them right now and come back to this one. There's no real order.
"Oh! He's beautiful!" Regulus gasped in delight.
Sirius held his new ginger kitten close to his chest. Mother had bought it for him when she took him to buy school supplies in Diagon Alley. Regulus dearly wished he could have come, but he wouldn't be starting Hogwarts until next year, so had had been forced to stay home.
"His name's Crookshanks!" Sirius announced.
"That's a weird name," Regulus giggled.
"Is not!" Sirius retorted. "It's a perfect name. Isn't it, Crookshanks?"
The kitten mewed its approval, and Regulus laughed again.
"Can I hold him?" Regulus begged.
"Sure," Sirius agreed.
He gently placed the kitten in Regulus' arms. It was tiny, warm, and so cute.
"I want a kitten!" he declared.
"You can get one next year," Mother promised. "When you go to Hogwarts. Now give the kitten back to your brother before you drop it."
Regulus sighed and returned the kitten to Sirius.
"Why can't I go to Hogwarts this year?" Regulus whined.
"Because you're not old enough," Mother reminded him. "Now, it's getting late. Both of you, to bed."
"Yes, Mother," they agreed.
"And I don't want to hear a peep!" she warned.
They ran upstairs and into their separate rooms. But neither had any plans for going to bed. Regulus instantly ran over to his mirror.
"Sirius, you there?"
"Right here!" Sirius replied. "And I have Crookshanks with me!"
Sirius appeared in the mirror, holding his new kitten.
"Yay! Hi Crookshanks!" Regulus called.
The kitten mewed.
"We should read the kitty story tonight, for Crookshanks," Regulus suggested.
"You mean Puss in Boots?" Sirius asked.
"Good idea," Sirius agreed.
He picked up a thick book and flipped through the pages until he found the story he wanted.
"Once upon a time…"
"Sirius! Sirius! SIRIUS!"
Sirius rolled over and slowly opened his eyes. The room was dark. It was the middle of the night! Why was Regulus waking him up?
"I'm up, I'm up," Sirius insisted sleepily.
"There's a monster in my closet!" Regulus announced. "A big scary giant!"
"There is not a monster in your closet," Sirius told him.
"Yes there is!" Regulus insisted.
"There isn't," Sirius assured him. "You just had a nightmare."
"It wasn't a nightmare! It was real! Something was making a scary noise and I opened the door and it was a huge giant!"
"A huge giant wouldn't fit in your closet," Sirius reminded his brother. "It was just a nightmare. I shouldn't have read you Puss in Boots so late at night."
"Stop saying it was a nightmare!" Regulus demanded. "It's real! Come see!"
Sirius dragged himself out of bed and into Regulus' room. He noticed that there actually were strange sounds coming from the closet. He was starting to wonder if maybe Regulus was telling the truth about the monster. But it was too late for doubts now. Sirius faced the closet door and slowly turned the handle.
When he opened the door, the closet seemed empty at first. Then, suddenly, a huge cobra sprang out of the shadows. Sirius screamed.
"You didn't tell me it was a giant snake!" he shrieked.
"It wasn't!" Regulus replied. "It was a real life giant."
As Regulus ran over to see, the snake suddenly transformed into a huge giant, like the one from Puss in Boots.
Sirius finally rushed forward to slam the door. Both eyed it with terror, but the monster didn't seem capable of breaking out. Yet.
"What was that?" Regulus asked.
"I think I've heard of something like that, in one of Father's books," Sirius admitted. "It changes shape to look like your worst fear."
"Let's go find that book," Regulus suggested. "Maybe it'll tell us how to get rid of it."
The two snuck down into the library.
"What book was it?" Regulus asked in a hushed whisper.
Sirius scanned a shelf, quickly finding what he sought.
He held out a thick volume entitled 'Moste Dark and Terrible Creatures of Magick.'
"That book looks ancient," Regulus whispered.
"I think it is," Sirius replied.
He flipped through the yellowed pages.
"Here it is!" he exclaimed.
Regulus read the passage over his brother's shoulder.
"The Boggart is a moste unnatural creature that doth take the forme of that which it perceives as the greatest fear of the one who doth observe it. By such power the boggart doth render its victims helpless. The moste cruel and deadly weapon against this creature is the sound of laughter, for laughter be the opposite of that which it hopes to receive, and as such a spell hath been created which doth transform the boggart's disguised form to one which shall invoke greater mirth. The spell is to be chanted thus; the wand must be pointed towards the boggart and the victim muste have a clear image of how he desire to change the boggart's form. When this is done, the word 'Riddikulus' is to be spoke in a clear voice, at which point, the boggart shall be translated."
"Do you think we can do it?" Regulus asked.
"Of course!" Sirius replied. "I got a wand today, remember? We can do anything!"
Regulus grinned as Sirius produced his new wand. Finally, they had the tool to do anything they wanted to.
Their newfound confidence faded quickly as they returned to Regulus' room. Sirius gripped his wand tightly in his right hand, while Regulus had a death grip on his left.
"You open the door," Regulus whispered.
"Why me?" Sirius asked.
"You have the wand," Regulus reminded him.
"You open the door and I'll use the spell," Sirius suggested.
"Alright," Regulus agreed.
He released Sirius' hand and crept towards the closet. It seemed like a century before his hand closed on the doorknob. He slowly twisted the knob and opened the door. Once again, the giant serpent snaked into the room.
"R-r-r-riddikulus," Sirius whimpered.
For a second, the snake seemed less substantial. Then, it was just as strong as before.
"Try again!" Regulus screeched.
"I can't," Sirius whispered. "You try!"
He tossed his wand to Regulus, who had no choice but to catch it. The boggart turned on him and again took the shape of a giant.
"Riddikulus!" Regulus screamed.
He desperately thought of the story of Puss in Boots. Puss had tricked the giant into turning into a rat, right? He just had to turn this giant into a rat and everything would be okay.
To his immense surprise, it worked. The giant suddenly shrunk down to the shape of a rat. Regulus and Sirius looked at each other in shock.
"We did it!" they finally screamed.
Behind them, the door of Regulus' room slowly began to ease open. Regulus was the first to notice, but his tensing up alerted Sirius to the fact that something was wrong. The two watched with baited breath as the door was pushed open, inch by inch.
"Crookshanks!" Sirius gasped with delight.
The kitten offered his owner a small nod, before advancing on the rat-shaped boggart. He hissed menacingly and the rat squeaked in terror. It tried to run, but it was already too late. A swift pounce and Crookshanks had the rat's neck between his teeth. A bite and a crunch and it was all over. Crookshanks offered his prize to his owner.
"You can keep it," Sirius told the kitten, trying not to make a disgusted face.
Crookshanks seemed to understand perfectly. The tiny kitten sat down in the middle of the floor and dug into its catch.
Sirius and Regulus looked at each other and shrugged. Eating a boggart probably wouldn't hurt Crookshanks. And neither of them wanted to take the rat carcass away from him.
"Night, Regulus," Sirius said finally.
"Night," Regulus replied.
Sirius crossed the hall back to his own room. Crookshanks followed as soon as he had finished his treat and licked his paws clean. Regulus waited until Crookshanks was gone before he fell into bed. He was asleep before his head hit the pillow.
He'd figure out how to explain the bloodstains on the carpet tomorrow.
Thanks for reading.
Author's Note 2: Theoretically, it is possible Crookshanks could have been owned by Sirius before Hermione bought him. If he was about a month old when eleven year old Sirius bought him, he would have been (according to my sources) twenty-three when Hermione bought him and twenty-six or twenty-seven when he last appeared in the books. While this is pretty old for a cat, it's not impossible. Furthermore, Crookshanks probably has a longer life expectancy due to the fact that he's half kneazle.