I did not expect this show to be good. All I expected it to be was nothing but fanservice and violence. Yes, there is fanservice and plenty of it; same with the violence. I did not expect it to be a decent family drama about the relationship between a mother and daughter.
While it is based on the Top Cow comic, the only thing the anime has in common with it is that there's an artifact called the Witchblade that gives the user (usually female) awesome powers and blades. The show takes place in a post-disaster Tokyo (not present-day NYC), and the current bearer of the Witchblade is Masane, a single mother with no memory of her past. She has to deal with trying to raise her girl without the government taking her away and fight various X-Cons - out-of-control mecha - and bearers of Cloneblades - women with fake Witchblades and work at the mysterious NSWF. There's also the fact that the Witchblade might kill Masane.
The characters are surprisingly three-dimensional. Most of the characters, from Masane and her daughter to the Cloneblade bearers and various members of the supporting cast, are well-developed and/or posses some form of likability. The interactions between the cast help sell the show. The fanservice and action are there and well-executed - just look at Masane getting aroused when she kills an X-Con while as the Witchblade and in her barely-there outfit - but that's expected. Also, the English dub is very well-done and is probably the best work Jamie Marchi, as Masane, has done.
In short, come for the sex appeal and violence. Stay for the plot.