Characters and their interactions relationships (ie mundane life) ARE AWESOME but sometimes slow. I like the sweetness and the quirks. The fights are good and well animated. The way they use their paper powers is cool! Tension/suspense is not necessary for this show. I would have been perfectly happy just watching them kick ass.
The reason the sisters fight ppl and the story surrounding that is usually bad. Also some of the choices the characters make in the fights really ruin the seriousness of their life and death struggles. Or maybe they don't really care that much if they die. Half the time their choice of work happens like that too.