To avoid worrying the Weasleys, Harry quickly left to find them.
After he was gone, Hermione asked with concern, "William, why were you in Knockturn Alley?"
"I bought a broken clock from Borgin and Burkes, the same type as the one the Weasleys have," William replied, pulling out an ebony clock from his ring.
"I'm planning to dismantle it, study its core magic, and modify it into a wristwatch."
The clock was too bulky to carry around, but a wristwatch was much more practical.
He intended to engrave the names William, Annie, and Hermione on it, with the watch's dial indicating locations like dormitory, great hall, classroom, library, safe zone, and home.
Additionally, he planned to incorporate a tracking spell to pinpoint their locations and ensure safety.
He would also embed one of Nicolas's communication shells into the watch.
Essentially, it was going to be a magical smartwatch with tracking and communication functions.
William was diving deeper and deeper into the realm of technical wizardry, combining his knowledge from his previous life with the alchemy he had learned.
The fusion was giving him endless inspiration for magical inventions.
One could even call his ideas revolutionary.
This high-end product would definitely be worth selling, though the first-generation models would be expensive and lack some features.
After all, how else could he release versions 2.0 and 3.0 in the future?
Perhaps a touch of artificial scarcity could boost sales too.
On his journey as a businessman, William was also venturing further and further.
The three of them had lunch at the Leaky Cauldron.
However, Hermione and Annie, having indulged in too much ice cream earlier, didn't have much of an appetite by lunchtime.
After their meal, they returned to Diagon Alley.
Soon, Annie was drawn to a shop window displaying flying brooms.
A crowd had gathered to admire them, and William could see that next to the Nimbus 2000 stood a brand-new broom: the Nimbus 2001.
In terms of performance, the Nimbus 2001 wasn't much better than its predecessor. It was more of a cash grab. But its sleek, fiery red finish made it undeniably eye-catching.
Most importantly, buyers could have their names engraved on the broom.
Annie's eyes sparkled with excitement, and even Hermione cast a few envious glances at it.
Though Hermione wasn't much of a Quidditch player, it didn't mean she didn't appreciate a beautiful broom.
A good broomstick was like a sports car. Even if someone failed their driving test multiple times and was nicknamed a "road menace," their desire to own one wouldn't diminish.
Besides, Hermione didn't even own a broom yet. For a young witch, a broomstick was practically a necessity.
"Brother, you haven't given me a birthday present yet!" Annie said and tilted her head towards the broomstick.
"Didn't I get you a bunch of study materials?" William grinned.
The little girl huffed, glaring at him. "That's not a birthday present!"
William ruffled Annie's hair.
The scene reminded him of a school event in his past life, a calligraphy competition. At the award ceremony, the first prize turned out to be a year of math tutoring, and the second prize was a stack of English practice sheets.
It was all a setup!
Annie dodged his attempt to mess up her hair and pressed on, "You borrowed my two-way mirror for research last time. You said you'd pay me for renting it by the day. Pay up!"
William casually pulled out a Sickle and handed it to her. "Keep the change."
Since he hadn't specified the rental price back then, one Sickle was quite generous.
Annie glanced at the broom's price tag, then at the measly Sickle in her hand. Her face fell.
"I remember giving you most of my pocket money," she muttered, "You even said it'd multiply tenfold in a year, like an investment."
That was true. Back in their first year, William and his friends had started the Akali's Mystery Shop. Their initial funds were tight, so William had persuaded Annie to invest her savings.
According to their original agreement, Annie's share was now worth thousands of Galleons.
"I lost it all. Business isn't always profitable," William shrugged.
In truth, he had opened a vault for Annie, storing a portion of the earnings there. The rest was reinvested in the shop. Annie just didn't know about it.
"You're a liar! Ginny told me they made a lot of money. Her robes were bought by Fred and George," Annie shot back, rolling her eyes.
"Alright, fine. We didn't lose money," William admitted shamelessly, "But I spent it on the it;s house and renovations. Plus, taking care of you and Hermione during the summer isn't cheap. The money's all gone."
Hermione blushed slightly. She felt she wasn't hard to take care of and could even skip snacks if necessary.
"That was my money?" Annie muttered.
The little girl's eyes lit up with a sly glint, "Dad's secret stash is hidden in the bookshelf, inside that thick book The Adorable Wisdom Teeth. You could steal it!"
William rolled his eyes. "Why don't you steal it?"
That money had long been discovered by Lyanna. Roy had sworn up and down it wasn't his, but Lyanna was keeping a close watch to find out who it really belonged to.
If William took it, it would implicate him, and he'd have to surrender it. He wasn't about to take the fall for Roy.
Annie sighed dramatically.
"Fine, I'll buy it for you," William relented.
Annie's face lit up with a radiant smile.
A few moments later, William emerged from the shop, saying, "The Nimbus 2001 will be delivered by an owl in three days."
Annie happily grabbed the receipt from him. As she glanced at it, she asked in surprise, "Two broomsticks?"
"Yes, one for you and one for Hermione."
"Oh, I don't need one. It's too expensive," Hermione quickly declined, shaking her head.
"It's your September birthday gift," William said seriously, "Think of it as an early present."
He knew Hermione had always wanted a broomstick. She might not fly high, but she still wanted to try.
"No, it's really too much," Hermione protested, unused to receiving such an extravagant gift.
William smirked and, trying not to laugh, said, "Alright, then besides giving up this year's birthday gift, you'll also have to sell yourself to me to cover part of the cost."
"Excuse me?" Hermione's eyes widened, her cheeks turning pink.
"I mean you'll help me brew potions for free. I don't always have time, and I'll need your assistance," William explained.
Most of the high-end potions sold in Akali's Mystery Shop were brewed by William himself. He genuinely needed a helper.
"Can I really help you?" Hermione asked excitedly.
"Of course."
William knew Hermione's skill level was exceptional. She had successfully brewed several advanced potions.
After all, how many students her age could make Polyjuice Potion?
With proper guidance, Hermione could easily become a Potions Master.
"'Wit beyond measure is man's greatest treasure'. Getting six years of free labor from you? I'd say I'm the one profiting here," William said.
Besides, the money for the broomsticks came from Annie's vault. She'd never know.
Unaware of this, Annie was lost in her own fantasies. "We could have a Quidditch match at home during the holidays! Let's see… Luna, Ginny, the twins, Cedric, Harry, the three of us, that's nine people. Ron can join to make it five versus five!"
William nodded in agreement. He was, after all, a legendary Quidditch chaos master.
Meanwhile, Hermione held the receipt, her bright eyes sparkling with emotion.
In the depths of her gaze, joy mingled with a hint of sadness.
What she really wanted to say was that she didn't need money. She would have helped for free.
For life, even.