Thanks to my-spirit-animal-is-the-impala for beta reading!
Disclaimer: I do not own Harry Potter.
"Ladies and gentlemen!" One of the twins shouted, it was hard to tell which.
"Gentlemen and ladies!" The other redhead roared.
"We have an amazing thing for you!"
"Muggle's Potion of Instant Gingerness!"
"As you can see, we've already tried it on ourselves…"
"…and got no result, so we need volunteers. Urgently."
"We are warning you, that's a real potion."
"At least, we really tried to make it so."
"Who wishes?"
"Who is brave enough?"
The Weasley twins looked around. Almost whole Gryffindor common room had put its affairs off after such a loud outbreak of them. With a habitually showy gesture showed they two bottles of a bright orange sparkling something.
Muggleborns' and half-bloods' faces split with smiles, while more or less pure-blooded looked quite anxious.
"Here you are with studying Muggle life from the wizarding point of view," Harry said, leaned to Hermione over her light reading. She didn't seem to listen – as she normally didn't, when the Weasley twins demonstrated a new harmless-looking creation, she needed to take up the role of a judge.
"It isn't an ordinary Fanta, is it?" she asked strictly.
"Of course not, or it wouldn't have any sense!" George said.
"The words Muggle's Potion are completely fair but we did work hard to make it gingering." Fred continued.
"Well, who's first?" George asked, ignoring Hermione's disapproval.
The Gryffindors started whispering, elbowing each other and nodding to the twins' direction. The pupils from Muggle families dared to taste the fastest, astonishing others with trusting and encouraging them to go and try, too.
After a couple of phrases like "it's ginger, why is nobody gingering" the ginger people were ensured to become brighter and owners of freckles were said to have more of them. Lee Jordan, who drank about a half-bottle, and, for some reason, Hermione, who took just one gulp, were accused of having darker suntan. When it was found out that all who drank "the potion" got orange tongues, the interest turned into panic. Lee, despite his 'suntan,' became visibly pale and, muttering "for any case, I may die", headed to the hospital wing. The twins cheered him up with shouts like "if you move that slowly, you'll die long before you reach the hospital" and then decided that the experiment on classmates wasn't enough. Everybody wanting was suggested to follow them, searching for a new victim in the whole castle's scope.
The company went through a half of the school and frightened even the ghosts but didn't manage to try the potion on anybody. They stopped on a corner where the big corridor from the Great Hall took a turn, and it gave them an idea.
"Let's just wait for somebody to appear."
"Somebody already seems to come."
"Exactly! For goodness sake, not a teacher…"
"I don't mind if it is one."
"Not McGonagall, please, not her-"
"Shut up!"
All in all, it was a teacher. Ones said a couple of rude words, others laughed, somebody cried or gasped. Obviously, the poor professor Lupin had never been met with this lot of emotions, especially in the middle of an empty corridor. He looked on the pupils' guilty faces and tried to smile.
"Something's up, lions?"
The twins, shaking with laughter, moved forward with an already full glass.
"A bit of experiment, professor."
"A Muggle drink which makes people ginger because of us."
"We solemnly swear we're up to no good or bad."
"If anything happens, sir, it's his fault." (This phrase was said by both of them in the same time, as they pointed at each other.)
Lupin smiled.
"Well, give that here."
He took the full glass from their hands, drank it slowly, followed with amazed looks, and knitted his brow a bit, holding his nose bridge with fingertips.
"Tasty but… prickling… Is it okay?"
"Yeah," Fred nodded importantly. "It'll be gone after a minute, so will the freckles."
"Freckles. Well. What else should happen?"
"Dunno," George muttered, looking on the followers' faces, as if searching there for an answer, then turned back. "It depends, as you can see. What do you feel?"
"I feel more like a fox than-"
He bit his lip suddenly but then smiled again.
"Than I am used to. Let's say like that. Well, thanks, it was funny. Have a good evening."
He continued his way along the corridor and tried to disappear as fast as he could.
"What the fox, George?"
"No idea, Freddy. So, who wants any extra, must bring some from the common room or follow us back there. I feel too ginger to go by myself."
A second-year, decided that the redhead mustn't be afraid of Weasley twins, moved to them from the crowd while returning.
"I've already seen you in the beginning of the year! Do you often make things like this?"
"Yeah. So often that my nose falls off two times a day."
"And will you do anything else with the Muggle food? For example, Sprite that makes people transparent or Mars Bars if they're-"
"Boy!" Fred looked offended. "That's we who serves as a bad example in here. Neither the caretaker nor the matron won't say thank you to anybody who makes up ideas for us."
"But I will! You just think, Fred – the invisibility soda! Dad will be happy…"
In the common room Fred and George treated their brothers and sister to Fanta, sent some more people to the hospital, helped themselves with the rest of "the potion" and spent the evening in making wise notes about surrounding people ("green-eyed, I warn you, don't take umbrage after all you've drunk, we didn't make you do that") without answering what was wrong.
"When will we say to them that "the potion" wasn't charmed at all?"
"Tomorrow maybe. We need all these poor guys to be back. Lee's still in the hospital, I suppose. Our dormitory is deserted…"
"And all our family is ginger. Will Mum be upset?"
"Well, not funny, that's rather hers and Dad's fault than ours. But d'you want to go do something what would really upset her?"
"As if I can say no."