Possibly interested, if I can think of an idea. 

Unfortunately, the only magical girl series I can think of that I've seen/read are Cardcaptor Sakura (and Sakura would probably be kind of difficult to play with monsters that actually need to be fought and killed) and an extremely silly series called G-On Project. I might be forgetting something though and I know I've got at least one other series sitting on my shelf.

Also, would PC villains be allowed?