In the Edo period in Japan, there was a shadowy group of vigilante ninjas - they did anything even murder as long as you paid.
One day your parents are falsely accused of a crime and murdered. Filled with sadness and anger, you make up your mind to revenge the death of your parents and remember there are assassins known as “the vigilantes.” Soon after that, you try to get in touch with them, but you don’t get any response.
Even as you are about to give up, one of the vigilantes appears in front of you and takes you to a tea house. After listening to your story, he suggests you join the vigilantes to take vengeance on the people who murdered your parents. After a moment’s thought, you decide to take his suggestion.