Regulus understood. He knew why Sirius had chosen the path he had, and he understood. He only wished that he were brave enough to do the same, to stand up and declare to the world that he too was in love, that he regretted that he hadn't the strength to throw his overbearing and obsessive mother off of his back, that he hated the Dark Lord and would do his utmost to stop him. But this had to be enough, he realized, as he wrote his note with a shaky hand.

It had started before he had left for Hogwarts. The year without Sirius had left him lonely and hollow, as if a part of him had been scooped out. Sirius wrote to him as always, but if anything, it reminded him more of their separation. But Sirius had come back in the summer, bursting with stories of his best friends James, Peter, and Remus as well as James' unfortunate crush on the most unattainable girl in their year, Lily Evans. Sirius had laughed it off, and started describing her friend, Marlene and Regulus knew. He had lived with Sirius his entire life, he was his blood. He understood immediately that this was no ordinary girl and simultaneously realized that Sirius was in deeper than he thought. His curiosity was sparked, and he spent many a night wondering about this girl who had taken Sirius' heart so easily from him.

Regulus was relieved when it was his turn to leave the house for Hogwarts. It had gotten more oppressive since Sirius had been sorted into Gryffindor. His mother had redoubled her efforts to make Regulus the perfect Black that Sirius could never be. Regulus longed to be free of her iron fist, yet he knew in the pit of his stomach that it was not to be. He knew deep inside himself that he was weak, that he would conform to his mother's will. And he was right. The distance between him and Sirius only grew as they lived in the same castle, but ran with very different crowds. They had been closer when Sirius had lived away at Hogwarts and Regulus was left at home, and an .

Regulus watched Sirius and his groups of friends, learning their names and their habits. James, who was obsessed with Quidditch and made Sirius laugh the belly laugh that Regulus used to hear because of him. Remus, who was always tired and carrying a book, but sometimes looked at his friends with disbelief and love, as if he couldn't believe that they were real. Peter, who was eager to please and happy to follow the rest of the group. Regulus felt jealousy gnaw at his gut as he watched their genuine friendship grow because Regulus felt more alone with his group of friends than he would ever feel on his own.

It wasn't until second year that he realized who the infamous Marlene was. He only recognized her because he saw her conversing with Sirius and realized from the look on his face that this was the girl that he knew held his brother's heart. He scrutinized her from afar, and soon realized that he saw her everywhere. He couldn't get her out of his mind, her dancing hands, her dark hair swishing as she walked and her tinkling laugh that spread warmth through his chest.

It wasn't until fourth year that he realized that he, like his brother, had fallen fast and hard for this girl that for all he knew, didn't know he existed as more than Sirius' miserable little brother who was going to join the Death Eaters as soon as he was out of school. He accepted his fate with resignation, acknowledging that he had chosen this path long ago, when he had asked the uncertain Sorting Hat to place him in Slytherin. Perhaps if he hadn't been such a weakling, he would have had a chance, but as he watched Sirius and Marlene fall in love with each other over again, he knew in his heart of hearts that the dice was loaded from the start. He could never compete with Sirius. He was a liar and a fake, going through with his mother's plans because he didn't have the spine to stand up to her.

By his sixth year, it didn't matter. He was in too deep. His brother had been kicked out, but Regulus hadn't had a proper conversation with him since he had been sorted into Slytherin. Regulus was on his way to becoming a Death Eater, with a date for his initiation being set in the summer. He spent the school year leading up to it memorizing her hands as they were interlocked with Sirius', her eyes as they lit up when they say Sirius, her lips as she smiled at Sirius' antics. Then she left Hogwarts and he never saw her again. He did his best to put her out of his heart, but love is a fickle thing. He still picked up on stories about her. She as living with Sirius. Regulus didn't have it in him to be jealous any longer. He was tired, exhausted of the pretense of his life and aged by the things he had seen and done. He hadn't the spine to get out, but he had never had the spine to commit these horrific acts. He knew it would come to a head soon.

He had heard the news yesterday. Marlene, the only girl his heart had ever seen, had been killed. She was, of course, a member of the Order of the Phoenix. She had died fighting he heard. That probably meant something to them, to the Order of the Phoenix, but to Regulus, all it meant was that she was no more. She had died, probably with Sirius' name on her lips and with not a thought his way. Regulus was proud of the mask he had on throughout the entire report, but as soon as he was alone, he cracked and cried for the first time in his short life. It was time to enact the plan. He read over his note once more.

To the Dark Lord
I know I will be dead long before you read this but I want you to know that it was I who discovered your secret. I have stolen the real Horcrux and intend to destroy it as soon as I can. I face death in the hope that when you meet your match you will be mortal once more.
-R.A.B.

Taking a deep breath, Regulus pocketed the note and barricaded his bleeding heart.