By coincidence, volume 1 of the manga arrived at my house a few days ago. I was putting in a large order with Amazon Japan, it popped up as a recommendation, and looked like an amusing ecchi fan-service comic, so I threw it in. Sadly, it’s aimed at a slightly older audience than usual, so there’s no furigana, which will significantly slow down my reading.
So, bearing in mind that I can’t just skim through it and get the gist of the plot, I would describe it as “the bastard child of DearS and Ikkitousen”. I’m not sure which parent it got the brains from, though.
Note: the heroine is Rushuna-scaled, enjoys bathing, and repels fog and other obscuring effects.