When the Doctor takes a human companion’s hand in his, it feels warm and slightly ticklish, rather like that time he was in China and had moxibustion cones placed all over his back. The single heartbeat feels erratic, incomplete, and crazed. It feels alien, and it reminds him of just how different they are. He thinks of how clammy and unnatural he must feel to them, and it scares him.
When he takes Romana’s hand, it is a gentle and familiar feeling, neither hot nor cold. Their hands mesh together almost imperceptibly, until it is no longer clear whose is whose, and at some point it ceases to matter while their four hearts pump past one another, mingling in a single, quadrifold rhythm.
When they run together and their hearts beat faster, their bodies grow hot together, a degree for a degree. They stay the same.
Sometimes the Doctor thinks about sex. Sometimes Romana thinks about sex. And when they do, what with them being telepathic and all, their minds go out into each other, and when heat and electricity converge and melt in one, heat and electricity converge and melt in the other. And this is almost as good as what comes next.
K9, being metal, is the same temperature at whatever he spends time in contact with. His innards are hot, yes, but his coolant systems are very effective, and the heat radiating outwards does not reach his outer casing. So he sometimes feels much like a harder, smoother Romana, but only when he’s been next to something with that temperature.
It’s not like Romana. There is some companionship, some happiness, some love that a robot dog just can’t give.
Now the War has come and gone. The radiation lives within the Doctor, burning out his brain in waves of pulsating heat. His organs seethe and roll in endless turmoil. Sometimes he feels an itch deep within his body, where he cannot scratch, and he is angry and deadly.
Now his companions feel almost normal to him. Now the heat of the sun is like a blessing, for the searing pain drives the itches and bubblings away. Now, for the first time, he feels the creeping presence of the learned court prosecutor, the unbearable and unfamiliar, terrifying desire to destroy, to burn like he is burning…and even when he regenerates, the radiation doesn’t leave him. If anything, it gets worse, for now there is the screaming anger of the residual Vortex within him, agitating the radioactive flames.
After a while, he stops looking for survivors, because he can no longer fathom a universe in which he is not alone, and sometimes he may not even want to.
And he knows that, if he met Romana again, the slightest touch of flesh unblemished by radiation and warfare, her hand on his hand, her cheek on his cheek, her tongue on his tongue…it would destroy, congeal and freeze him.
It would freeze him solid, oh God it would be so cold, so cold.
And he would stand there.
He would stand there for a very long time. While the universe turned, and the Vortex sang and screamed, he would stand stock-still, frozen by the cold touch of his love, the touch that once made home for them in the midst of adversity.
And he knows that, even if he was frozen and remained frozen until he crumbled to dust and entered the Vortex forever, even if he stood there until the universe crashed down around him…
For a single touch of those hands, a single hint, no matter how slight, a single salvific whiff of forgiveness…it would be worth it. It would be worth everything.