This is Ginny's outfit, but hers is black.

Blaise's outfit,

The Great Hall was packed with visitors of all kinds. Everyone from the Minister of Magic to the entire Weasley family. Ron wasn't allowed to be at the event, seeing as he'd been classified as a danger to the students, but that didn't stop him from sipping some Poly Juice potion and sneaking in anyways.

He had to see Hermione's performance, after all, and if he could find a way to ruin it? All the better. 

Professor McGonagall stood on the stage to address the crowd.

"Good Evening ladies and gentlemen," she began. "And welcome to our House Unity Competition. For this project, every student n the school was sorted with a member from another House, and tasked with preparing a song and dance routine to perform in from of all of you. Over the past few months, our students have embraced their singing voices, and have put aside their differences to put on this show. You might be pleasantly surprised at how well some of these students have gotten along. I know I am."

As McGonagall's speech continued, Neville Longbottom peeked out into the crowd, the rest of the students crowded behind him.

"Can you see the audience?" Someone hissed.

"Is it full?"

"Who's out there?"

"Is my dad here?"

"Please tell me Ron isn't out there," Hermione pleaded. 

"I don't see him." Neville admitted. "But the rest of the Weasleys are here."

"Oh Merlin." Ginny swore.

"Looks like I'll be getting ripped apart by the Weasley boys today." Blaise commented. 

"It's a full house out there!" Neville exclaimed. "The Minister of Magic's even here!"

"Oh MERLIN." someone called out anxiously. "I'm gonna puke!"

"Aim for Professor Flitwick, that would be hilarious!" Someone replied.

"Oh shoot, it's starting!" They all dashed back to their places backstage, except for Blaise and Ginny, seeing as they were going first.

"For our first act of the night," McGonagall announced. "I give you Ms. Ginerva Weasley of Gryffindor, and Mr. Blaise Zabini of Slytherin preforming a song called "Don't Threaten Me With a Good Time."

The audience applauded and McGonagall took her seat as the curtain rose, revealing Ginny and Blaise in dramatic poses with their canes, their top hats tilted down to hide their faces.

But then they snapped to life as music began to play and they started to sing the song.

"Alright, alright, Alright, alright, Alright, alright, it's a hell of a feeling though, It's a hell of a feeling though, Alright, alright, it's a hell of a feeling though, It's a hell of a feeling though!"

Then Blaise took over the song and Ginny resumed her frozen pose. 

"Who are these people? I just woke up in my underwear, No liquor left on the shelf, I should probably introduce myself." He tossed up his cane and caught it again, showing off his outfit. "You shoulda' seen what I wore, I had a cane and a party hat, I was the king of this hologram, Where there's no such thing as getting out of hand, Memories tend to just pop up, Drunk pre-meds and some rubber gloves, Five-thousand people with designer drugs, Don't think I'll ever get enough ."

"Don't think I'll ever get enough," Ginny echoed. Then they both jumped in with the chorus, their dance movements in complete unison. 

"Champagne, cocaine, gasoline, And most things in between, I roam the city in a shopping cart, A pack of camels and a smoke alarm, This night is heating up, Raise hell and turn it up, Saying If you go out you might pass out in a drain pipe, Oh yeah,"

"Don't threaten me with a good time!" Blaise yelled out before resuming the song with Ginny. 

"It's a hell of a feeling though, It's a hell of a feeling though, Alright, alright, It's a hell of a feeling though, It's a hell of a feeling though."

Then Ginny took over the song, and Blaise retreated. 

"What are these footprints? They don't look very human like, Now I wish that I could find my clothes, Bedsheets and a morning rose, I wanna wake up, Can't even tell if this is a dream, How did we end up in my neighbors pool, Upside down with a perfect view? Bar to bar at the speed of sound, Fancy feet dancing through this town, Lost my mind in a wedding gown, Don't think I'll ever get it now," 

"Don't think I'll ever get it now" Blaise echoed, returning to the song as the chorus hit again. 

Champagne, cocaine, gasoline, And most things in between, I roam the city in a shopping cart, A pack of camels and a smoke alarm, This night is heating up, Raise hell and turn it up, Saying If you go out you might pass out in a drain pipe, Oh yeah, don't threaten me with a good time!"

The canes were ditched and Blaise grabbed the lapels of his suit jacket, looking innocent as he kept singing and Ginny stopped. 

"I'm a scholar and a gentleman, And I usually don't fall when I try to stand. I lost a bet to a guy in a Chiffon skirt, But I make these high heels work."

"I've told you time and time again," Ginny took over. "I'm not as think as you drunk I am, And we all fell down when the sun came up, I think we've had enough."

They both came in together, belting out the last bits of the song. 

"Alright, alright, it's a hell of a feeling though, It's a hell of a feeling though, Alright, alright, it's a hell of a feeling though, It's a hell of a feeling though, Champagne, cocaine, gasoline, And most things in between, I roam the city in a shopping cart, A pack of camels and a smoke alarm, This night is heating up, Raise hell and turn it up, Saying If you go out you might pass out in a drain pipe, Oh yeah, DON'T THREATEN ME WITH A GOOD TIME!"

They struck epic poses as the song hit its last beat and the audience erupted into applause. 

"Boom." Blaise said sassily.

"Up top, Zabini." Ginny replied, holding out her hand. The two did a ridiculously complex handshake and then ran off stage, grinning. 

"That was AMAZING!" Harry declared.

"Not bad, Blaise." Draco insisted.

"That was a great way to start this off." Hermione agreed.

"I pity the people who follow us." Ginny proclaimed. "Because we just ROCKED HOGWARTS!"