Class change into Speed Gunner as Sleeping Beauty and/or Kaguya or Marshal as Alice and/or Cinderella. Use the Merchant trick in the Jail Tower detailed above and buy a Proto Gun for a Speed Gunner or a Howl Eater for a Marshal. Have the Blood Maiden in question learn an AoE attack such as Amber Red and put extra points into it. While the 31 MP cost of Amber Red is expensive early on, the high damage and speed of the Speed Gunner and Marshal classes allow you to destroy all enemies in one or two turns, assisted by an overpowered weapon equip. Make sure to keep careful watch over the Corruption level. Blood Maiden running a setup like this move faster than Jack, meaning they can Blood Skelter before you get the chance to clear it. If they go Blood Skelter and use AoE attacks on your party, it's going to hurt.