A simple line in a rather innocuous book sealed Regulus' fate. Draco had become weirdly obsessed with soul magic again, likely hoping to kill two birds with one stone - help Harry with his horcrux and help Regulus get his body back. Win-win.

Regulus was peering over Draco's shoulder, re-reading a book they'd found over a year ago. They must have read the line before and dismissed it, but seeing it again was damning.

Manipulating a soul via magic is specific to the caster. Any operation involving a soul can only be changed, recast, or undone by the original witch or wizard.

Dread poooled in his gut. Over the last year, Regulus had plenty of time to ponder his situation. Draco had felt bad about not being able to do more research with him, but Regulus had nothing but time to think. Draco had class? Think about how to get out of the ring. Draco was practising spells for the cabinet? Think about the runes again. He had puzzled through a lot watching the world go by, but by the end, he had been grasping at threads, hoping his understanding was just off, and that's why he couldn't puzzle out a way to undo the magic holding him.

"Do you suppose this means you could undo your own horcrux?" Draco asked, finishing the end of the section.

Regulus jumped slightly, getting pulled out of his thoughts. He hoped Draco didn't notice anything amiss.

"I assume so, but I wouldn't expect someone who split their soul ever to do that. No matter how nice you ask, I doubt the Dark Lord will remove the soul piece off Harry and let him live."

Draco curled his lip and continued to read. Regulus resisted the urge to crawl into the nearby sofa and sulk. Initially, they had naively assumed that since James was dead, they could alter the magic of the ring however they pleased. They knew it would be tricky, but now he had to face the reality of it being impossible. James had indirectly trapped his soul. Only he could get him out, and since James was dead…

If Regulus had been asked two years ago about how he felt about being trapped in the ring, he would have been thrilled just not to be dead. Being stuck beside a disillusioned teenager wasn't exactly fun, but it was a hell of a lot better than death. Besides, it wasn't all bad. He had been able to help both Draco and Harry, but it was different now. Each day, he felt a little worse watching life without being able to interact. He wasn't lonely because he was actually alone. By definition, he was always with Draco, but being unable to be seen by most people, let alone heard, was isolating. He hadn't felt the touch of another person since he died in the cave, and Kreacher had let go of his hand. He couldn't live like this. It wasn't living.

Despite the knowledge, he wasn't ready to give up his soul yet. He still wanted to help Draco. He wanted to help Harry. Hell, he even wanted to destroy some horcruxes while he could. When he died in the cave, he was convinced he was doing something significant, only to find out over a decade later that it was pointless. The horcrux he'd gone after wasn't destroyed, the Dark Lord was still around, and worse, James had died by his hand. It had been crushing that his final act for redemption was futile, but he supposed this was his chance to redo it properly.

He watched Draco as he poured himself into his reading, probably trying to escape the last few days. Regulus wished he could have seen what happened with Dumbledore and coached Draco through it. He wasn't sure Draco grasped how he had altered his life entirely in one moment. They were in a precarious position; the Order would be after him and the Dark Lord was unstable, and Regulus knew he could kill Draco over a misplaced look. They had to keep making progress if they wanted to accomplish anything before Draco was dead too.

"We probably don't want to undo the horcrux," Regulus said. He had to keep Draco pointed towards helping Harry instead of himself.

"What do you mean?"

"We want to destroy it ultimately. We should be focusing on ways to protect Harry's soul."

Draco took a moment to think. "So we need a way of identifying souls. That way, we can focus on either protecting Harry's or just destroying the horcrux." He trailed off and flipped to the chapter list of his book for a new lead.

Regulus sank further into his chair. He just had to keep him focused on helping Harry. It shouldn't be too hard. They could discuss his fate later once Draco had a bit more hope.

They had a week of peace before the Dark Lord started returning to the manor. He didn't call another meeting via the mark; rather, certain individuals were pre-arranged to be there. Draco and his parents were usually invited to watch the proceedings.

It was a bit surprising how hyper-focused he was on Harry. He had the ministry ready to crumble, and every damn meeting was about Harry's movements. Every Order member had a tail on them in hopes that they could gather hints about how Harry was getting to his aunt and uncle's for the summer. If he got to their house, the Dark Lord wouldn't be able to touch him. Something the Dark Lord was going to great lengths to avoid.

One meeting had been focused solely on getting Harry a ministry-ordered auror detail. It was, frankly, a genius plan. All it would take is one corrupt auror willing to apparate Harry away, and the Dark Lord would have him. Regulus almost asked Draco to warn Harry about it, but the fear of Draco getting caught silenced him.

And Draco would get caught. Draco couldn't hide his emotions. He wore every expression on his face, and while Regulus tried not to blame Draco, it would lead to disaster soon enough. There was no way the Dark Lord missed the way his brows would furrow or how his lips tightened at the mention of Harry. Draco was practically screaming his discomfort on his face.

The Dark Lord never asked Draco anything or gave him another task, but Regulus figured that was just another test. He wanted to see Draco's initiative. He wanted Draco to ask to go after Harry like he did Dumbledore. He wanted Draco to prove that it hadn't been a fluke that he'd killed Dumbledore. But Draco wasn't showing initative, and Regulus couldn't ask that of him. Even if it would make things easier, he didn't think Draco's soul could handle casting another unforgivable at the moment.

Weeks had passed since leaving Hogwarts, and Draco wasn't showing signs of getting better. His birthday passed without Regulus even realising, and Draco didn't bother testing his magic now that the trace was gone. Regulus and Barty had spent the night doing every spell they thought of the first summer they turned seventeen. It was disheartening that Draco didn't have the same excitement.

The manor, consistent with every other time he'd been there, was suffocating. Draco couldn't leave the manor; it was still too risky with Dumbledore's recent death. Lucius was still recovering from Azkaban and soured every room with his presence. Honestly, Regulus didn't care about Lucius, but he hated how it was affecting Draco. Once again, Draco had to face that his father was a fallible git. It was probably good in the long run, but Regulus hated the way Draco stressed about it.

Narcissa was single-handedly keeping the house together. He suspected she had made a deal with the Dark Lord to help Draco. Snape had claimed that he had convinced the Dark Lord to protect Draco from blame, but Regulus didn't believe that was the whole truth. She had been scheming with Bella. She had probably made sure Yaxley went along, and she probably took the first opportunity she could offer the house to the Dark Lord for mercy for both her husband and son.

The past was repeating itself. His mother had offered everything to the Dark Lord, including himself and the Dark Lord had pushed them all into destroying themselves. And so here he was, watching another teen spiral because he failed. It was too depressing to just watch happen. He needed to give Draco some hope.

"Can I teach you something?" Regulus asked as Draco closed his current read.

"Sure," Draco said blandly.

"Get out two pieces of parchment."

It was silly what he was having Draco do, but he genuinely hoped it would settle Draco's nerves. He felt nostalgic as he instructed Draco through a series of charms to cast on both pieces of parchment. Draco cast each without question.

"Now, think of a word or phrase."

"A phrase?" Draco asked confused.

"It can be anything."

Draco looked at him blankly, then said, "Nimbus 2001."

Regulus snorted. He sometimes forgot how Draco was just another teen who loved quidditch. "Say it and castRevelaro." Draco did.

"And you are done," Regulus said proudly.

"Done with what?"

"A way to communicate with Harry when you see him again."

Draco stared at him, mouth open. "Lacewings. You might want to shut it."

Draco snapped his jaw shut and looked down at the paper. He tested it, having deduced how it worked by the combination of spells. He wrote on one, then gripped the other saying the phrase, 'Nimbus 2001.' His handwriting appeared, and the second he let go, both pages turned blank.

Draco gave a small smile, gently folded the parchments, and stored them in his robes. They both knew that it wasn't a guarantee that Draco would be able to get the parchment to Harry, but neither mentioned it. It was an option and that's all that mattered at the moment.

Draco returned to reading, shoulders a little less tense.

Regulus didn't know if he was just paranoid or if Draco was getting more suspicious of him. He had been off since reading that he could never get out of the ring. He was slower to respond, and he knew he was letting the defeat show on his face.

Even if he hadn't yet, Draco would pick up on it soon. He was smart. Regulus would only be able to come back if James brought him back, and considering James was six feet under, he wouldn't be coming back anytime soon. Regulus had never wanted to be a ghost. Life was painful enough that he didn't need to cling to it, and he needed to warm Draco up to that idea.

He was sick of feeling on edge about Draco uncovering the truth. One evening, he just decided to go for it.

"There is something I need to tell you." Draco looked at him and waited. He took a breath and finally said it. "I can't come back."

"What are you talking about?"

"Do you remember the book you read about soul magic?"

"What about it?"

"Only the caster can undo the magic."

"But you -" Regulus watched Draco's face fill with horror as he realised. "But he's dead!"

Regulus winced. "Hence why I can't come back. If death was enough to cut off his magic, my soul would have already been released."

"That can't be right."

"I know you have been studying, but I doubt you know more than the scholars. Tell me one instance when someone undid magic on a soul they didn't cast."

Draco ground his teeth. "There must be some."

"You're right. They all ended with the soul destroyed. Or if not destroyed, severely damaged."

"No."

Regulus scoffed. "You can't just wish a different reality."

"We've done impossible things before," Draco protested.

"And do you really want to go through all of that again? Let's find some more students to almost off. Who do you want to kill this time?" It was a cheap dig, but he needed Draco to understand. "This is different. Killing Dumbledore was improbable. Bringing me back is impossible."

"You've already given up haven't you?"

Regulus sighed. "I can't come back, but I haven't given up. I want to see Harry rid of that horcrux. I want to help you make it through another year. I want to save Sirius. You can't deny that from me. If it goes poorly with the veil, oh well, it was going bad anyway."

Draco turned away, not entertaining the conversation. He was stubborn like he had been with everything Regulus tried to get him to understand, but he just needed time to think it through. Regulus only had time to think and when Draco caught up, he would come around. He had before.