I have never heard of Valkyrie Drive before, oh, an hour ago when I read this comic.
So now I have done my Due Geek Diligence and watched the first episode.
I enjoyed it. I enjoyed the premise. It appeals to my inner 15-year-old. And I feel weirdly guilty about that. Like, it's SO stupid and such obvious fan service, and yet there I am, digging it.
(Reminds me of Devadasy, which I have never seen, but have heard about. If you're unfamiliar, Devadasy is about giant mecha which are piloted by men, but powered by female orgasms. So the whole time the mechs are fighting, there's a woman inside climaxing over and over. And SURPRISE TWIST, the male and female protagonists are also brother and sister. And yes, she's the power supply for his mecha. At least, that's what I remember from reading the descriptions many years ago.)