After placing Rose on the console room floor, the Doctor was quick to send the TARDIS into the vortex, his eyes flickering over to where Aries was on the jump seat as Mickey mopped her for head with a damp cloth the TARDIS had provided. Although he knew that Mickey was only a friend of Aries, there was still a small spark of jealousy in his gut at the sight of another male taking care of his Nesdra. He was just thankful that having spent a week by Aries side had managed to quell his jealousy down so it wasn't so overwhelming.

Once the TARDIS was drifting in the vortex, the Doctor was quick to make his way over to his Nesdra's side. He could already feel his regeneration starting, but he wanted her to be awake when he did so. He didn't want to go without saying goodbye. Mickey handed him the cloth and moved away, allowing him to take over. The Doctor glanced at Mickey, "What happened?" he questioned, wanting to know what had put in Nesdra in danger again as he brushed a hand over Aries' cheek tenderly.

Mickey swallowed, his eyes wide, "Rose returned, said you sent her away. She got this crazy idea of trying to open the console when she noticed some graffiti. I," he looked away, remembering what Aries had said about causing the TARDIS pain, "I didn't know that it was hurting her as I tried to help Rose open the console. The chain snapped, but Jackie had another vehicle. We had hooked it up and had started trying again."

"And what about Aries?" the Doctor asked, trying to keep his anger under control at the knowledge that Rose had tried to force open the Heart of the TARDIS as he placed the cloth on the floor, not even taking notice when it vanished. He had to tell himself that Mickey didnt know what could have happened.

"She appeared in the console room. I didn't even know she was there," Mickey explained, "She was furious at what we were doing and unhooked the chain. I was fighting with Rose as she had never told us that Aries had been hurt, that she was unconscious for a week. The next thing I saw was a blinding golden light surround Aries before she stumbled and I tried to reach her. Then the TARDIS started moving and Rose was just standing there, the light entering her eyes."

The Doctor looked down at Aries, "Oh, Aries," he murmured as he brushed some hair from her face, "Why would you do that?"

"I couldn't let you die," Aries spoke up as her eyes fluttered open, "I couldn't let you deal with them on your own."

The Doctor winced and looked away from her, moving his hand away from her cheek as he continued to fight back his regeneration.

Aries grabbed it as she frowned at his reaction, her brows furrowing in confusion. "What is it?" she asked, seeing his face contort in pain before noticing the hand she was holding glow golden. "No," she breathed, trying to get up as a wave of dizziness washed over her, "No, no, no!"

"What is it?" Mickey asked, noticing Aries panicked expression at the sight of the Doctor's glowing hand.

Tears gathered in Aries eyes as the Doctor explained, "I absorbed all the energy of the Time Vortex, and no one's supposed to do that."

"This wasn't supposed to happen," Aries told him, "She was supposed to help me save you," she closed her eyes and turned her head away as a tear rolled down her cheek, "It's all my fault."

The Doctor placed his hand on Aries cheek, turning her head to face him. He brushed away the tear before kissing her forehead, "And you did save me," he whispered, causing Aries to open her eyes in confusion, "Ever since I met you." He grimaced in pain again and made to move away from Aries, unsure how long he could keep fighting against his regeneration, but Aries stopped him.

"Please," Aries pleaded, placing a hand on his cheek and looking into his blue eyes that were filled with so much pain and sorrow, "Don't go," she continued to plead as another tear fell.

Mickey watched in rather confused. He didn't know too much about the Doctor and was starting to grow alarmed at how much emotion Aries was showing. In the six months he had known her, he had never seen her cry, and now she was doing just that and acting as if the Doctor was dying.

The Doctor smiled sadly at Aries, "You know I can't stop it," he murmured, resting his forehead against hers as he closed his eyes. The urge to kiss her was there, but he wouldn't, he couldn't. She didn't know about their bond, she didn't know what it would do, what it would mean. "But I'll always be with you," he told her as his hand tightened around hers.

Aries closed her eyes in pain, knowing the Doctor was right. She squeezed his hand as she swallowed, knowing that the Doctor was saying goodbye, that there was no way of stopping his regeneration. She pulled away from him slightly so she could look into his blue eyes once more and managed a small smile, "I'm gonna miss this face," she choked out as more tears fell.

The Doctor managed a laugh at her words as he pulled away, knowing that he needed room to regenerate. Aries hand dropped from his cheek and he grabbed it with his free hand and gave them both a squeeze as her smile brightened a little more before he let them go and moved back to the console.

"What's happening?" Mickey asked as he watched the Doctor's face crease in pain as the Time Lord gripped the console tightly, his hands once again glowing golden.

Before Aries could answer, Rose spoke up, "What happened?" the blonde asked as she sat up on the console room floor, a frown on her face after seeing Aries and the Doctor's interaction. She had no idea what they were talking about, but she didn't like how close they had been.

The Doctor glanced at her, "Don't you remember?" he asked, both a little glad and disappointed that the blonde didn't remember.

Rose's frown deepened as she tried to remember, "It's like there was this singing."

"That's right," the Doctor said, "I sang a song and the Daleks ran away."

Aries choked out a laugh at his words and the Doctor couldn't help but grin at her.

"I was home. No, I wasn't, I was in the TARDIS," Rose said, trying to figure out what happened before she turned to Aries with an angry look, "You stopped me from saving him," her eyebrows furrowed as she continued to think, "Then there was this light. I can't remember anything else."

Aries stood up off the seat when she noticed the Doctor's condition worsening, but he shook his head at her, not wanting to hurt her when he regenerated. "Aries. My Aries," he said softly, causing Aries to still in shock at his declaration, not missing the significance on the word 'my', "There was so much I wanted to show you, so many places I wanted to take you. Barcelona. Not the city Barcelona, the planet Barcelona. I think you'd love it. Fantastic place. They've got dogs with no noses. Imagine how many times a day you end up telling that joke, and it's still funny."

Aries smiled sadly, "It sounds wonderful," she told him softly.

Rose scowled at the red head, "Then, why can't we go?" she asked the Doctor, rather put out as once again he seemed only focused on Aries.

The Doctor glanced at her, "Maybe she will," he said, having noticed over the last week how much Rose didn't like Aries and had planned on dropping her off if she didnt stop, "And maybe I will. But not like this," he continued, looking back at Aries as Mickey helped support her. He didn't feel the spark of jealousy he would have normally gotten at the sight, rather glad that there was someone who could help Aries when he couldn't.

"You're not making any sense," Mickey told him, still rather unsure as to what exactly was happening. Aries seemed to know, but that didn't surprise him as she seemed to know quite a lot of things others didn't.

"I might never make sense again," the Doctor told him, "I might have two heads, or no head. Imagine me with no head," he narrowed his eyes at his Nesdra playfully when she snorted, "And don't say that's an improvement," he told her with a small smile before he continued, "But it's a bit dodgy, this process. You never know what you're going to end up with..." he doubled over in pain.

"Doctor!" Rose exclaimed as she rushed towards him.

"Stay away!" the Doctor told her, holding up a hand as he backed away.

Mickey looked between Aries and the Doctor again, seeing the tears running down Aries face as she stared at the Doctor, but made no move to approach him. Seeing that she was upset, but not trying to help him, the young man stayed beside her as he allowed her to lean against him. She knew what was happening, so he'd follow her lead.

"Doctor, tell me what's going on," Rose demanded.

"He absorbed the Time Vortex," Aries said, her voice wavering as she spoke, "No one's meant to do that. He's dying," she stated, her voice cracking at the thought. As much as she knew that he'd be fine, that regenerating was just part of him being a Time Lord, she couldn't help but feel like this was her fault and she was losing someone she cared for. As much as she knew he would still be the same person, she had learnt from both Alistair and Sarah that he would change in more ways than just his features. He would become a completely new person.

"Can't you do something?" Rose asked.

The Doctor looked to his Nesdra , seeing her sadness. "Yeah, I'm doing it now," he said as he searched his mind for something he had never searched for. As much as he had wanted to in the past, as much as he had wanted to reach out to her mentally, he had never done so. But seeing his Nesdra in the state she was in, he wanted her to know about their link, even if he wouldn't tell her what it was. "Time Lords have this little trick, its a sort of a way of cheating death. Except it means I'm going to change, and I'm not going to see you again," he told them as he continued searching his mind, "Not like this. Not with this daft old face. And before I go-"

"Don't say that," Rose cut him off, causing him to frown at her.

The Doctor looked back to Aries, a small smile making his way on his face as he found what he was looking for, "Aries, before I go, I just want to tell you, you were fantastic. Absolutely fantastic," Aries smiled at him, remembering the words he had said to her so long ago, "And do you know what? So was I."

Aries watched him throw his head back as a golden light burst out of his body. They all covered their eyes, the light too bright to look at, but Aries jumped in surprise when she heard the Doctor's voice in her mind.

I'll never forget you, my Aries, my Nesdra.