Venus Versus Virus is the type of fiction I find most annoying: interesting (if not unique) at first glance but mediocre in execution, potentially great plot threads converted into generic crowd-pleasers, likeable characters and endearing relationships utterly wasted on the dull plot.
Lucia and Sumire's friendship -- especially given their functions as gate and key -- should have been the emotional focus, but instead we get a ridiculously fast romance which was nothing more than a transparent plot device (and not a very good one, either); the main villain and his motives were obvious from the get-go, but the story pretends it's some great mystery, which was annoying in the extreme; Sumire's love interest has no personality whatsoever, to the point that I prefer his nasty alter-ego; the entire cast's dreams and motivations were far too typical and trite to be even remotely intriguing.
So why the not-so-low rating? Because, as I mentioned before, I'm really fond of the characters for some reason, and Sumire and Lucia make lovely battle partners. Also, all power to important platonic relationships (even though they're still secondary to the romantic one)!
Give it a try if you have nothing better to do, or have a real hankering for "Female fighters." Otherwise keep looking, because this premise has been handled better elsewhere.