Briefly, Erena was Azone's foray in to the "action girl" genre, similar in concept to BBI/Takara's CyGirl/Cool Girl line. While most of the other Azone/Obitsu hybrids were based on licensed media property characters or a real person in one case, Erena was (as far as I know) an original character. I guess Erena is some kind of Hollywood-style "butt kicking machine" and possibly a cyborg, since there's a nice brochure included in the box that seems to explain it all. Alas, I don't read Japanese (GASP! What kind of Otaku am I?) so I don't know all the details.
At any rate, I recently happened upon a boxed Erena- Mission 2 for a pretty reasonable price and I just had to buy her. While I certainly wouldn't mind owning Mission 1, this is the version I most wanted. Especially funny to me is that she not only comes in her de rigueur action girl tube top, leather mini skirt and tall boots but she also has a full disguise as a cleaning lady, complete with a toilet plunger! You know at least a bad guy or two is going to get owned by said plunger. Of course, there also the regulation action girl BAP- Big Ass Pistol- for taking out foes in a more conventional manner. No idea if it comes with the bottomless magazine or if she actually has to reload. Also, no info on whether it can shoot down airplanes and helicopters, blow up cars and shoot escape holes through walls, floors and roofs.
I hope to get some better photos of her in the near future (these were taken during a brief lull while my kids were both napping) but these will have to do for now.