A/N: I was absolutely dying of feels after re-watching School Reunion, so here we are...
Rose made it through their outing at the cafe, before she couldn't take it any longer. "How many of us have there been– travelin' with you?" she demanded, as she followed the Doctor onto the sidewalk in front of the cafe.
"Does it matter?" he replied, still walking.
Rose knew why it mattered, even if she refused to admit it to herself."Yeah! It does, if I'm just the latest in a long line!"
"As opposed to what?" He paused and turned to face her, shoving his hands into his pockets.
For a moment, she couldn't think of a response, and they stood in relative quiet. "I thought you and me were… But I obviously got it wrong."
The Doctor's eyes flickered away, to a point somewhere over her right shoulder, and he opened his mouth to interrupt, before thinking better of it.
"I've been to the year five-billion," Rose went on, "But this… this is really seein' the future. You just leave us behind– that what you're gonna do to me?" Her voice wavered and her eyes shone under the street light.
The Doctor brought his eyes back to Rose's. "No," he said firmly, his voice hard and steely. He couldn't bear to lose her. "Not to you," he added more quietly.
"But Sarah-Jane…" Rose protested, "You were that close to her once, and now… Ya never even mention her. Why not?"
The Doctor hesitated before answering, taking a moment to collect his thoughts. "I don't age. I regenerate. But humans decay– you wither and you die. Imagine watching that happen to someone you–" He cut off.
For a second, Rose had thought he was going to say it. Actually say it. "What, Doctor?" she prodded gently, hopefully.
"You can spend the rest of your life with me," he said instead, "But I can't spend the rest of mine with you. I have to live on. Alone." The Doctor paused, remembering all his past companions, and the pain was clear on his face. "That's the curse of the Time Lords."
"I said forever," Rose replied adamantly, "and I meant it." With that, she grabbed him by the lapels and pulled his mouth to her own.
-l-l-l-l-l-
Sitting on the back of the car, Sarah-Jane looked up in surprise, as she saw Rose pull the Doctor in. She watched as the Doctor froze in surprise, then relaxed into her.
She was glad to find that she didn't feel even the tiniest bit jealous.
Unfortunately, Mickey couldn't say the same.
