It was a mystery to him how Nyssa had ended up here, even more than the others.
Usually, he never went back. Never. Too many goodbyes to drown in, if he answered every plea for his return.
Maybe she had impressed him. She could not have been aboard the TARDIS for more than an hour, helping Adric build a device to jam the Source, yet somehow she had grasped his ship's basic systems. It had taken rare genius to attune the Source's telepathic communications relay to contact his TARDIS all the way back on Earth.
She had asked for his help. Or had he asked for her help? His time as the Watcher was a blur, a blip in the timestream in which the next incarnation overlapped the previous. He only knew he had gone to Traken to bring her away, driven by instinct and blind urgency, sensing that he needed her skills, her sensitivity, to help bind him to the body awaiting his soul. She had made no sound when he folded ghostly arms around her, dragging her across the void.
She made no sound now, but the hum of her dreams was like the brush of a night breeze through pine needles at the edge of hearing. Profoundly restful, a Zero Room in his own bed.
It was a mystery to him how Nyssa had ended up here, although she was not the first.
She was the first to grow up under his watch. That made this difficult. He had traveled with humans so long that it was easy to mistake her for the girl she had been, although her own agelessness, not Gallifreyan but more than human, was beginning to show.
He wondered how long she would outlive Traken. His arms tightened around her, feeling the faint beat under thin silk, frail flesh.
Maybe it was because Nyssa understood the TARDIS systems more than most. With grudging anxiety, he had watched her head and shoulders disappear under the console, small hands caressing cables and junctions that could kill if she were careless. He had let her in there before he had let her in here.
Maybe it was because she had known him before he was truly born, had been waiting for him when he sat up, his new body shedding its chrysalis. She had met his eyes the moment he opened them, and there he had seen understanding as well as concern. It had been a difficult regeneration, but for once he had the care of a knowledgeable ally, not only clueless humans to see him through.
It was a mystery to him how he had held out so long. Habit and Time Lord mores notwithstanding, he could no longer regret giving in. It had ceased to make sense to slip back to his room at the end of a difficult and dangerous adventure, while another door clicked shut at the far end of the hall.
Better by far to come back to this: her small form safe beside him, fervent heat huddled against his chest, ringlets tickling his throat, sleep-loosened features close enough to kiss.