The rest of the summer passed in a state of quiet, profound healing. Nagini, for the first time in over half a century, was simply allowed to be. She stayed with Ariana in the shielded London flat, a safe harbor where the world could not find her. Her recovery was slow. Her body was weak, and her mind was a tapestry with great, gaping holes where decades of her life should have been.
Ariana became her gentle guide, her patient historian. She didn't press or pry. She would simply sit with her in the evenings, telling her stories—not just of the dark lord, but of the world she had missed. She brought out Muggle books, played her music from her past life's memories, and showed her films on the television. She was reintroducing a mind, piece by piece, to the concept of a world that was not defined by pain, loneliness, and the cold, whispering presence of a fractured soul.
Nagini, in turn, began to remember. Small things at first. The taste of a certain tea. The feeling of rain on her skin. The face of a dark-haired, troubled boy named Credence who had shown her kindness in a Parisian circus. The memories were fragmented, but they were hers. She began to speak more, to smile, her dark eyes losing their haunted, wary look and gaining a spark of their old, fierce intelligence.
Dumbledore was a frequent visitor, arriving quietly via the Floo network. He would sit with Nagini for hours, the two of them old ghosts from a different war, speaking of people and places long gone. He was helping her heal, but she, in turn, was helping him. She was a living link to his own past, a reminder of the mistakes and the friendships that had shaped him.
In mid-August, a large, official-looking owl from the Ministry arrived for Ariana. It was her N.E.W.T. results. She opened the parchment with a calm lack of ceremony. As she had calculated, the results were perfect. Twelve N.E.W.T.s, all graded 'Outstanding'. A small, personal note from Griselda Marchbanks, the head of the Wizarding Examinations Authority, was attached, calling her performance "the most profound display of magical knowledge in the history of the examinations."
Her formal education was, for all intents and purposes, complete. At sixteen years old, she was now one of the most qualified witches in Britain.
The day before they were all set to return to Hogwarts, Dumbledore called a final meeting. Harry, Ron, Hermione, and the Weasleys arrived at Ariana's flat, joining Sirius and Remus. The reunion was joyous, but there was an underlying question: what now?
It was then that Dumbledore laid out the new arrangement.
"With the start of term tomorrow," he began, his eyes twinkling, "we have a rather unique situation. Miss Dumbledore," he gestured to Ariana, "has, as of this morning, officially completed her Hogwarts education with marks that may never be equaled."
A round of stunned applause and whoops from Ron and the twins filled the room. Hermione beamed, her face a picture of pure, unadulterated pride in her friend.
"As such," Dumbledore continued, "she will not be returning to Hogwarts as a student. To have her sit in sixth-year classes would be an absurdity and a waste of her time." He paused, letting the statement sink in. "However, her presence at the castle is, I believe, strategically essential to our efforts in the coming year. Therefore, I have created a new, temporary position for her."
He looked at Ariana, a warm smile on his face. "Miss Dumbledore will be returning to Hogwarts as a special guest of the Headmaster. She will be granted private quarters and will be undertaking a… direct, post-graduate apprenticeship under my personal tutelage."
The 'apprenticeship' was, of course, a cover story. A brilliant one. It gave Ariana a legitimate, unassailable reason to be at Hogwarts, with full access to the castle's resources, without being bound by the rules and schedules of a student. It made her an independent agent, operating under the direct protection and authority of the Headmaster himself. She would be free to continue her research, to train her friends, and to direct the secret war from the heart of the fortress.
"And," Dumbledore added, his gaze shifting to the quiet, dark-haired woman sitting beside Ariana, "she will not be coming alone. Her great-grandmother, Nagini, who is recovering from a long and difficult illness, will be staying with her in the guest quarters as a ward of the school, under my personal protection. Her presence here will be known only to those in this room."
The plan was perfect. It provided a safe haven for Nagini, kept Ariana at the center of the action, and gave them all a secure base of operations for the year to come.
And so, when the Hogwarts Express pulled out of King's Cross Station on September first, Ariana was not in the student carriages. She, along with Nagini, traveled later that evening by floo, arriving directly in the Headmaster's office.
They were given a comfortable, spacious suite of rooms in a quiet, unused tower of the castle. As Ariana helped Nagini settle in, she looked out the window at the familiar, glittering grounds of Hogwarts.
She had arrived here as a lost girl in another's body. She had become a student, a friend, a warrior, a healer, and a strategist. Now, she was something else entirely. She was an independent power, a secret grandmaster in a war against the darkest wizard of the age.
The final Horcrux, the one living inside her friend, was the last piece on the board. The final confrontation with Voldemort was an inevitability. The school year was beginning, but for Ariana Dumbledore, the endgame was already in motion.