Her room on the TARDIS is not like the room she had in her flat. Rather, it's an approximation of what he - what the ship - thinks she would like. Three mirrors on the dresser. She's not sure if that's meant to be comforting or an insult. With him it can sometimes be both.
For the first week or so after she moved in, she half-expected to open her door onto a black void. Vaguely unsettling, to think that when they're not traveling, or she's at Coal Hill, they're just...floating through space. She's reassured by the constant white noise hum of the TARDIS engine. And his presence, somewhere in the distance. Is he working? She can hear music sometimes.
The Doctor doesn't sleep, she knows that much.
In the meanwhile, he still drops her off at her job, and they still go on adventures together. Wednesdays becomes every other day becomes every day, as soon as she's home.
Home, there's an odd thought. Open the TARDIS doors and slog her stuff on the floor and run towards the Doctor to give him a hug, tell him about her day. Yes, that's gum in my hair - you should see the other guy. It's a nice routine. Less lonely, to have this to come back to instead of an empty flat.
It's really not that much different than what they did before. It's just that now they're...in the same space. There's an extra weight to things that she can't quite define. She can feel his eyes at her back when she says goodnight and heads off to her room.
***
Today is particularly terrible. Difficult students bouncing off the walls. The ringleader roping everyone else in until there's utter chaos. It's worse than that time she and the Doctor were on that sand planet and had to deal with the crabs or the lobsters or the - Clara can't really remember now, she's just seeing red. Just so eager to get home and be done with this.
A cave with troglobites makes for a remarkably effective stress cure. Especially with the Doctor at her side, nattering on about the different species they're seeing. "Oh, and this one, Clara, is particularly rare." She smirks at him and he recedes into himself. Just like the bright purple troglobite she just made the mistake of poking with a stray elbow.
That night, though, she's surprised at how she can't sleep. Clara supposes that she's still too wired from the day. Voice hoarse from yelling at her students, even the nice ones who were really just at the wrong place at the wrong time. And tomorrow she has to face it all again. She curls up, thumps her pillow, counts to twenty and back down again. It's no use.