The Fourth Doctor
"Regenerating?" he gaped at Princess Astra as she stood - inexplicably - in the console room. "What are you talking about regenerating, only Time Lords regenerate! Look, it's awfully nice to see you, Princess Astra, but..."
"Romana."
"Romana? Ah!" and though he didn't show it, his hearts did a backflip in loving glee as Romana - his Romana - stood before him, her radiation sickness naught but a memory, regenerated into a body of which she (being a rarity among Time Lords) had the power to alter to her whim, finding a form to find her.
And she looked, he thought, amazing.
"Ahh!"
"Shut up, K9!"
Destiny of the Daleks, Part 1