Female Ninjas Magic Chronicles 4: Rebel Forces at the Threshold
くノ一忍法帖 IV 忠臣蔵秘抄 / Female Ninjas Magic Chronicles 4: Rebel Forces at the Threshold (1994)
The female ninjas have to stop an alliance from carrying out their dastardly deeds, which includes bizarre ninjitsu sex magic to aid them in their quest.