One evening, at dinner, Dumbledore interrupted the meal. "Students, we have a treat this evening. Mr. Harry Potter is attempting to change his classes to take Arithmancy and Ancient Runes. He has a project he would like to demonstrate for us. The Gryffindors and Hufflepuffs looked up in anticipation. The Slytherins joked amongst themselves.
The Ravenclaws snickered, with the exception of a downcast Luna Lovegood, who wasn't wearing her radish earrings, having been deprived of their possession one week ago. The Ravenclaws were expecting something pedestrian, such as a runic torchlight, or a useless spell to turn someone's hair Weasley Red.

The doors to the great hall slammed open. Harry Potter entered, wearing what appeared to be one of Gilderoy Lockhart's more fashionable suits, cut down to size.

While walking to the head table, Harry spoke. "Hello everyone. Let me introduce myself to you. Some of you know me as Harry James Potter, Order of Merlin, First Class, honorary member of the Dark Forces Defense League, and one-time winner of Witch Weekly's Best Smile Award." Harry smiled and a twinkle momentarily lit up the room.
"It's coming out tomorrow." All of this was true. Harry was chagrined to hear from Hermione about his awards, another thing Dumbledore never told him about, and he cut a deal with the Witch Weekly editor only yesterday - an exclusive interview in return for the best smile award and the secret wordless charm used by award winners to show off their smiles.

Hermione was embarrassed by memories of her second year crush on Lockhart. Ron was wondering what the bloody hell was going on. Colin Creevy was taking photographs, having been asked to do so by Harry that afternoon.

"I admit that I was at a loss as to what I should do for my project. Then I learned that a very dear friend of mine was suffering some difficulties at the hands of her house mates. I was told that nothing could be done about it. Nothing at all." Harry looked at Luna. Luna looked up to Harry. McGonagall had the decency to look embarrassed.

Staring at Luna, Harry continued, "I disagreed, and I do so very much enjoy a good challenge."

"You all know me as the 'Boy Who Lived.' Others know me as just 'Boy' or even 'Freak'. But a few, a very few, know me as the Heir of the Marauders." Snape sneered. Lupin smiled. Lupin's dog Snuffles smiled. McGonagall and the other professors shuddered. Dumbledore's eyes twinkled. Fred and George stared in awe.

"For the record, I am the son of James Potter, also known as Prongs. I am also the god-son of Sirius Black, known as Padfoot, who, by the way, is an innocent man. I'm likely the heir of that fucking rat bastard Wormtail, also known as Peter Pettigrew, who probably hasn't changed his will because he is that stupid, but that traitorous wretch doesn't count anyway. And I'm very likely to be the heir of Moony, whose identity shall yet remain secret. I shall be his heir provided that he doesn't get off his haunches and impregnate everyone's favorite metamorphmagus." Lupin blushed, but not nearly much as Miss Nymphadora Tonks, seated to his left, who blushed from head to toe, in cycling colours, her eyes not daring to reach above her dinner plate.

"As I am the Heir to the Marauders and the Marauders as a rule do not like bullies, without further ado..." Harry stopped at the head of the Ravenclaw table. He clapped his hands together, knelt down, and slapped them onto the floor. A network of intricate runes formed around the Ravenclaw table and Professor Flitwick's chair. Harry stood up, pulled his wand out from behind his ear, and with a swish and a flick, yelled out "SMURFIFY!"

All of Ravenclaw yelled out, their forms twisting into blue perversions of nature, as did the form of Professor Flitwick, who was different from his students only by the addition of a white fluffy beard. Only Luna was unaffected.

Harry again waved his wand and yelled out, "Sing, you blue bastards, sing!"

Music played, and against their will, they sang.

"La, la, la, la, la, la,
sing a happy song La, la, la, la, la, la,
smurf the whole day long

Smurf along with me
simple as can be
Next time you're feeling
blue just let a smile begin
Happy things will come to you
so smurf yourself a grin"

Snape, who looked exactly the same as always but whose robes were transfigured to a dark brown leaped up and cried out, his right fist waving wildly, "Ooh, I hate smurfs! I'll get you, I'll get all of you, If it's the last thing I'll ever do!" Lupin quietly knocked Snape unconscious with a stunner.

"La, la, la, la, la, la,
now you know the tune
La, la, la, la, la, la,
you'll be smurfing soon."

The singing stopped. Cho Chang stood up. She repeatedly tried to say "Professor Flitwick!" but it came out as "Papa Smurf! Papa Smurf!"

Flitwick replied, "Just wait and see, Cho Smurf. Let's see what Mr. Potter wants."

Harry continued. "I'll tell you what I want, my little smurfs. You're going to get off your bright blue butts and smurf up Luna's belongings and return them to her in pristine condition or replace them with new things. Then I will restore you to your prior forms. And you will never, ever, steal from my friend Luna or harass her again. You have until this time tomorrow. If you don't do it, you'll remain smurfs forever. I'll have a conversation with the Sorting Hat, and House Ravenclaw will be no more, having been replaced by House Smurf, and every smartass sorted into Ravenclaw from now on will be smurfified. Permanently."

"So get smurfing. Now!" The students of House Smurf, err Ravenclaw, jumped up as one and ran for the doors. Except Luna.

"Headmaster, here are my notes." Harry pulled a thick scroll out of his pocket and placed it on the head table. "You won't find the countercurse. I'm saving that for tomorrow. Is this good enough to get me into Runes and Arithmancy?" Dumbledore was dumbfounded. Flitwick, surprisingly taller than normal, was pinching at his blue skin. Snuffles was wagging his tail. Lupin was alternating looks between Harry and Tonks. Tonks was still blushing, a smile forming on her face. McGonagall struggled to maintain her composure. She spoke up to say something to Harry, but he ignored her. Instead, Harry approached Luna who stood up to meet him.

Harry gave Luna a small box. She opened it. It contained a pair of earrings. "Cabbits? My favorite. Thank you Harry. Thank you so very much." Luna hugged Harry deeply and put on her new earrings. "You didn't have to do this, you know."

"I didn't have to not do this."

Luna looked up at Harry expectantly. "Luna, my darling, would you care to dance?" With a wave of Harry's wand, ballroom music filled the great hall. Harry climbed atop the Ravenclaw table and lifted Luna up to him. The couple then proceeded to dance a waltz amongst the plates, platters, and silverware, ignoring everyone else in the great hall. Every so often, as Luna smiled, her earrings cried out softly, "Myaa!" This caused Luna to smile again, causing her earrings to make even more happy noises and causing Luna to smile even more. That caused Harry to smile, with a twinkle of light momentarily filling the room. Whenever that happened, Luna smiled again and the cycle continued.

"Harry, why didn't you turn me into a smurf?" Luna, while very happy, managed to stop smiling for a moment to look a little disappointed.
The fluffy ears of her cabbit earrings drooped down.

"Everyone knows there's only one girl smurf, Luna, and I just couldn't imagine you being a boy." Harry leaned towards Luna and kissed her cheek.