Geneva’s used to feeling…sub-par around the Inspector. It’s not that he does it on purpose, in fact most of the time she thinks it’s just gut reaction. Gut reaction to mock her or roll his eyes or let his upper lip twitch so subtly. She’s not an idiot, but she is stubborn and all she wants to do is show the Inspector that she can do this, she can be a good companion even though she’s not as big or tough or male as those that have come before her.
You see Geneva knows that the Inspector becomes icier and icier when she can’t quite force the Darsit doors open or hold back whatever alien they happen to be fighting. She also thinks though, that if the Inspector just let her explore, if he explained how space-time worked more than a non-committal wave of his hand- then she’s sure she could astound him.
It hits a point one day, the pair running from something with huge green spikes protruding from all their major joints, that she doesn’t quite reach the Darsit in time, that she can’t quite pull the doors open fast enough, and with a screech and a surprising amount of orange goo (she thinks it might be blood), the Inspector, her Inspector is on the ground; light building in his palms as it rapidly fades from his eyes. She knows it isn’t her fault, well only her fault, but she’s holding the only man she’s ever wanted to impress this much and is seeing disappointment, feeling him twitch away from where her hands are holding him.
That’s how he ends up regenerating: with her, tears on her face, hiding against that stupid red door that she couldn’t open in time.