Summer, 1967. Regulus turned six.
In the House of Black, six meant you were entitled to your own study space. And so, the top-floor attic at 12 Grimmauld Place welcomed a new occupant.
Regulus had questions he couldn't let go of.
Wizarding medicine could heal injuries with ease, yet the human body remained fragile. Why?
If magic could repair flesh, could it also strengthen it?
And if so, why had no one spent centuries studying this in any serious way?
He sat cross-legged on a cushion, eyes closed, turning his awareness inward.
Magic flowed through him along fixed, familiar routes, like channels carved long ago.
The books all said the same thing. Magic was born from the soul and released through the body.
That was it.
No one bothered to ask how the body itself shaped the process.
It was like knowing water came out of a pipe, but never wondering whether a wider, smoother pipe might let the water flow faster and steadier.
In the original story, this had been a blind spot of the author.
Living inside it, Regulus realized it was a blind spot of wizarding civilization as a whole.
He moved beneath the skylight. Slanted sunlight poured in, cutting bright shapes across the floor. He held out his hand, letting the light rest on his palm, then closed his eyes again.
This time, he tried something different.
Without casting a spell, without words or wand, he guided his magic toward his right arm.
Simply asked it to go there.
At first, it resisted.
Magic felt almost willful, slipping back into its usual paths, refusing deliberate redirection.
Regulus didn't rush it.
Patience was something an adult soul had in abundance.
He imagined magic as water, his intent as a riverbed.
Slowly digging.
Slowly guiding.
Two and a half hours later, it worked.
His right arm felt warm. Not heat exactly, but fullness. Energy gathering beneath the skin.
He clenched his fist.
His grip felt… just a little stronger.
Over the next few days, Regulus shifted into pure observer mode.
He watched everyone in the house through the lens of perception.
Walburga's magic was powerful but unstable. When her emotions spiked, her magic surged and trembled with it.
Regulus noticed something else. When she maintained complex protective charms for long stretches, she would unconsciously rub her temples, her face turning pale.
Conclusion: the burden of magic expenditure was ultimately carried by the body.
Yet it never occurred to her to strengthen the body to increase that tolerance.
Orion's magic was deep and heavy, controlled with precision.
But once, after his father finished casting and lowered his wand, Regulus caught the faintest tremor in his fingers.
Barely noticeable.
Still there.
A fatigue response from long-term, high-intensity spellwork. Magic could suppress it, but it always came back.
Sirius, however, was the best comparison of all.
One afternoon, Sirius tried out a new charm in the garden. He lifted pebbles into the air and arranged them into a constellation. He managed it, but only just.
When it ended, Sirius collapsed onto the grass, panting, sweat soaking his hairline.
"So tired…" he muttered to himself.
Regulus walked over and handed him a glass of water. "Used up a lot of magic?"
Sirius gulped it down, then only nodded, offering a quiet, "Mm."
Regulus knew the reason for the silence. After what had been said at dinner last time, Sirius didn't want to talk to him.
Regulus didn't push. He turned and left.
A week later, deep into the night, Regulus knocked on the door to Orion's study.
"Come in."
Orion was reviewing documents, the candle at the corner of his desk casting light over his exhausted face.
The Ministry had been under immense pressure lately. From overheard fragments, Regulus suspected it had everything to do with that rising figure.
The Death Eaters' earliest form had already begun moving, staging attacks. The Ministry buried the news, but the old families all knew.
"Father."
"Go on." Orion set down his quill and rubbed between his brows.
"I've been thinking about something," Regulus said, taking the chair opposite him. "Where exactly is a wizard's magic stored?"
Orion paused. "That's a foundational question. Magic originates from the soul and is released through the body."
"But the body isn't just a conduit, is it?" Regulus pressed. "If the body is injured, magical output suffers. If the body is strengthened, shouldn't output improve?"
"In theory, yes," Orion said. "A healthy body supports spellcasting. But once basic health is reached, further physical enhancement provides negligible benefit."
"Has anyone tested that?"
Orion was quiet for several seconds. "Not that I know of. Traditional thought holds that magical potential is innate. Training improves control, not total capacity."
"But what if capacity is limited by how much the body can bear?" Regulus leaned forward. "Like a cup. It only holds so much water. But if we make the cup bigger…"
"The soul is the cup," Orion cut in. "Not the body."
"Are you sure?"
Orion studied his son for a long moment. "No. But that's the accepted theory."
"Accepted doesn't mean correct," Regulus said softly.
He continued, "Father, how many things in the wizarding world were once 'accepted' and later proven wrong? For example, it was once accepted that Muggles were inferior, but now their technology—"
"That's enough." Orion's voice carried a quiet warning. "Regulus, I know you're clever. You think differently. But some questions are not yours to ask yet."
"Then when should I ask them?" Regulus didn't retreat. "When Voldemort comes knocking?"
Orion shot to his feet.
"Who told you that name?" His tone hardened.
"No one," Regulus said calmly. "I listened. Cousin Bellatrix. Mrs. Malfoy. You and Mother, speaking in low voices.
You call him 'the Dark Lord,' 'that man.' But I found his name. Tom Marvolo Riddle. He calls himself Voldemort."
Orion slowly sat back down, fatigue weighing his words. "You shouldn't know these things."
"But I do," Regulus replied. "And I know more. He's recruiting. Gathering power. Pure-blood families are choosing sides. The House of Black will have to choose eventually."
After a long silence, Orion asked, "Are you afraid?"
"No," Regulus answered without hesitation. "But I need strength."
Orion closed his eyes. When he opened them again, a long time had passed.
"The question you asked earlier, about the body and magic," he said. "I can tell you this. Someone in the Black family studied it.
My great-grandfather, Arcturus Black. He believed wizards relied too heavily on magic and neglected the body."
Regulus held his breath.
Someone had seen it. And it was his own ancestor.
"He conducted experiments," Orion continued, his voice darkening with memory. "Using magic to strengthen the body, then using that enhanced body to contain more magic. The theory was a reinforcing cycle."
"What happened?" Regulus asked, unable to hide his urgency.
"He lived to one hundred and thirty-seven," Orion said. "One of the longest-lived Blacks. And he was powerful.
But in his later years, he went mad. His notes are filled with chaotic symbols and warnings. The final entry reads: the container is too solid. What's inside can't get out. I've trapped myself."
Regulus stared, stunned.
You could… trap yourself like that?
"What does it mean?" he asked bluntly.
"I don't know." Orion shook his head. "The notes are sealed, buried deep in the Restricted Section. I tried reading them once. Three pages in, and my head felt like it was splitting. They weren't meant for ordinary readers."
Regulus's heart hammered.
Someone had researched it. There were results. And a price.
"I want to see them."
He knew Orion wouldn't agree. He asked anyway.
"No." Orion refused without hesitation. Then he paused. "At least not now. Arcturus's final state was… very wrong.
Promise me, Regulus. Don't seek out those notes on your own."
Regulus stayed silent.
He didn't want to promise.
"Promise me," Orion repeated, his voice heavier now, almost pleading.
"…I promise."
Orion exhaled, knowing that promise might not last long, and waved him away. "Go."
Back in the attic, Regulus sat in the dark, turning everything over in his mind.
Arcturus Black. One hundred and thirty-seven years old.
Madness.
A container too solid.
Had the body, strengthened to its extreme, ended up imprisoning the soul instead?
But what if soul and body truly fused, with no boundary between them?
What then?