"What do you think of the view?"
"Cliché."
The top of the clock tower wasn't exactly designed for visitors, and the spotlights around Big Ben were a bit harsh on Thess's eyes. Even so, the nighttime illumination of the tower emphasized its Gothic architecture, giving the building a ghostly grandeur.
Around them, the city's lights glittered on the Thames, turning it into a silvery ribbon winding through the city, while the massive London Eye, with its hypnotic colors, tried to monopolize attention as it turned slowly in the distance.
"Thessaly Wood, you're really a hard girl to impress," Orion said.
"Is this a duel or a date?" Thess replied.
Orion walked slowly to the edge, scanning the surroundings, looking for something.
"How's this going to go?" Thess asked impatiently.
"How do you think it's going to go?" Orion said, turning back to face her.
"I don't know; I'm not exactly familiar with the underworld of Quidditch duels. I was thinking maybe like a joust, but on broomsticks instead of horses and lances."
Orion smirked, grabbing his broom that was leaning against the wall. The two Firebolts had been previously enchanted to keep them hidden from Muggle eyes.
"We're having a race," he said, mounting his broom.
"A race? Really?" Thess said, mounting hers as well.
"Really."
They gained a bit of altitude but stayed close to the tower, using it to shield them from the wind so they could still talk.
"I'm curious because you've seen me fly. I don't know if you heard, but I've got a new speed record."
"I've seen you fly, and you're terrible. You fly like an amateur. I'll show you how a professional flies."
"I'll show you who's the amateur. Where's the finish line?"
"There," he pointed to the London Eye across the river. "Hard to miss."
"Okay. What's at stake? Who stays on the team?"
"Do you want to leave the team?" he asked, orbiting her broom.
"No!" she shouted, trying to be heard over the wind.
"Do you want me to leave the team?" he asked, this time looking her straight in the eyes.
"I thought you wanted me gone," she said, quieter now, looking away.
"That depends."
"On what?"
"How fast you learn."
The London Eye was only 160 yards away—a short distance, but still more than twice the size of a Quidditch pitch.
Thess launched first, which Orion allowed on purpose, much to her irritation. She wasn't used to flying a top-tier broom like the Firebolt, so the acceleration almost threw her off. By the time she regained her posture, she had already passed through the spokes of the giant wheel.
She looked behind her, searching for Orion, but couldn't spot him.
"You didn't even see when I passed you, did you?" he said, now in front of her.
"Where did you come from?" Thess asked, confused.
"Let's try again—this time to Trafalgar Square," he said, pointing to the distant column in the square, clearly visible under the floodlights.
"No cheating this time," Thess warned.
"You're the boss."
Thess took off first again. This time they would cover about a thousand yards. Confident in her victory, Thess glanced behind her to see how much of a lead she had on Orion, but again, he was nowhere to be seen. When she turned back to face her goal, Orion was waiting, bored, by Horatio Nelson's statue.
"That's not fair! You're Apparating!"
Orion sighed. "Let's go again. St. Paul's Cathedral. I'll go ahead. Let's see if you can spot me this time."
They took off again. Orion launched a fraction of a second earlier, and this time Thess saw what he was doing. He wasn't flying in a straight line like she was. He was following a spiral path, like a screw, incredibly fast. That's why she hadn't seen him pass before—he must have gone above or below her.
"That doesn't make sense," she said when she finally caught up to him at the top of St. Paul's dome. "Flying that way, you're covering way more distance than I am. How are you still beating me?"
Orion smiled. "Finally, you're asking the right question."
"What do you know about flying?" Orion asked before taking a bite of his kebab.
"It's what happens when you get on a broom," Thess replied, mouth full.
The two of them were sitting at a plastic table in front of a Turkish food stand at the Southbank Centre Food Market. The waitress had found the two brooms resting on the third chair a bit strange, but this was London, so she'd decided not to ask.
"No," Orion said, wiping his mouth. "I mean the physics of it."
"Physics? I thought it was magic."
"Okay, let's start from the basics," Orion said, pulling out his phone. He fiddled with it for a moment until an image appeared, showing a vertical cross-section of the planet Earth. "We're surrounded by a massive layer of gas called the atmosphere."
"No need to be that basic," Thess said, signaling for a refill of her orange juice.
"Don't interrupt," Orion continued, flipping to the next image. "Birds fly, planes fly, helicopters fly, all following the same principle: creating more air pressure beneath them than above. This is called aerodynamics."
"Brooms obviously don't follow that principle."
"Obviously."
"Excuse me," a tourist interrupted.
"Yes?" Orion asked.
"Are you two street performers?" the tourist asked, holding his phone in a way that suggested he wanted a photo.
"No," Orion replied.
"Yeah," Thess jumped in, "we're cosplayers. Just came from London Comic-Con."
The tourist's eyes widened in surprise and delight, and Orion tried to hide behind his juice cup.
"That's awesome! What are your costumes?"
"We're witches."
Orion nearly spat out his juice.
"Cool," the tourist said, gesturing to his phone. "Mind if I take a selfie?"
"Not at all."
The photo turned out well, even with the odd pout Orion made.
"I didn't know Comic-Con was happening," Orion muttered.
"Neither did I," Thess smirked.
"Back to the point. Brooms use a gravitational charm similar to Wingardium Leviosa. Therefore, they're not aerodynamic."
"They look pretty aerodynamic to me," Thess said, glancing at the Firebolts, which indeed had sleek lines reminiscent of a McLaren's bodywork—if McLaren cars were made of wood.
"That's an illusion caused by design choices. They're made to look fast, but none of those sleek, stylish lines matter when there's a wizard sitting on top of them."
The next diagram showed how air interacted with a wizard on a broom.
"So, as you can see," Orion continued, "a broom is only as aerodynamic as the wizard riding it. Unlike a plane, which slices through the air with grace, the wizard basically slams into it."
"Wait," Thess interrupted. "Is this a PowerPoint? Did you make a PowerPoint to teach me this?"
"Of course not," Orion said. "I... found it online."
Thess let him continue, pretending to believe he'd found a PowerPoint on flying broomstick aerodynamics online.
"Anyway, when we fly in a straight line at high speed, we're essentially crashing headfirst into a wall of air, which, depending on our speed, can be as strong as a brick wall. The longer you fly in a straight line, the thicker that invisible wall becomes. And the thicker it is, the more drag and pressure you feel. In short, you lose speed."
"That's not how I feel when I fly," Thess recalled the tunnel of wind she'd felt when she caught the Snitch in her last match. "I'm always accelerating."
"Not as much as you could be. You think you're flying fast; most people do. But the truth is, to unlock the full speed potential of a broom, you need to fly in curves. That way, you slice through the air instead of slamming into it."
"So that's why you fly in spirals," she concluded.
"That's why I fly in spirals," he agreed.
"That's an interesting concept," she said, loudly slurping the last drops of her juice.
"That's the Quidditch metagame. You've seen it in action—you know it works."
"Alright, let's go," she said, standing up and grabbing her Firebolt.
"Go where?"
"Back to the sky. I want to try this maneuver."
"Wait," Orion said, trying to access his phone's payment app, but before he could manage it, she had already Disapparated. "Damn it," he muttered, tossing a Galleon onto the table before following her.
"Again," Thess said, back at the top of Big Ben. "This time, for real."
"You still haven't given up on this idea? This isn't a duel."
"Are you chickening out?"
Orion mounted his broom and got ready.
"Let's go farther this time," he said, pointing to the pyramid-shaped building near London Bridge. "All the way to The Shard."
"I don't want you giving me any advantages."
"You won't get any."
They both took off simultaneously, spiraling in concentric circles. Even with the concealment charm, a few cameras around the city captured some UFO footage that night with a rather peculiar shape.
The feeling of speed was unlike anything Thess had ever experienced. Her heart felt like it was going to leap out of her mouth—or maybe that was the kebab. Either way, the pressure of the wind on her face was much lighter than during her final match against Slytherin.
When she raised her head, she could see Orion directly above her, although the concepts of "above" and "below" shifted with every fraction of a second. Still, she noticed him pulling ahead.
She could still win. All she needed to do was give it her all, just like she had in the final match. And that's what she tried to do—but something held her back. Something inside her.
In the final, she had risked her life for the victory, and if it hadn't been for Ginny's protection spell, she would have died. But Ginny being there had been pure luck. Thess hadn't expected anyone to save her that day, and she had taken the risk anyway.
"Why did I do that?" she asked herself. A thought without words, because words couldn't catch up to that speed, just like the second question: "Why can't I do it again?"
Orion won.