It's been 9 years when you stopped killing. You're the most dangerous samurai in the whole continent, having a name 'Samurai Slayer' to put it into words, a 'Battosai'.

You've killed so many people that you can't count over the past years you became a slayer. Ever since you were a child, even being a girl, you were trained due to your shown skills at a young age because you were once a slave, your family was killed by some swordsman. So ever since, you have been sold as a slave and ended up being a slayer.

Being a 16 years old, you have killed all you want, thinking it would make the world peaceful, if all people die, then suffering won't cause people. That was your mindset, it was understandable because of your living. You were known far and wide, the Battosai, the killer, the slayer.

But you met a guy, a noble guy. Knowing you're the slayer, he loved you with all his heart, the way you always put cold and poker face because it was too normal for you, he understands and make you feel loved. But then, he was killed. You felt nothing, but inside, you felt like merging to kill those who had killed him, only that way, you will feel the burning rage in your heart and mind.

After that, you have brutally killed those people and realized something. With that, you started to decide you won't kill again with your hands. You started to become a wanderer. As 9 years passed by. The era of killing, samurai and slayers had come to an end, and the way the name Battosai was not heard anymore. They said she just vanished.

You were now 25 years old, wandering with your reversed blade. It was meant not to kill, the type of katana. Your cold and poker face was now in contrast by how you acts. You were more cheerful and acting dense, just living your life as a wanderer.

But then, you met a royalty, a prince. Frederick, he's much younger, he's 23. He had suspected you were the Battosai, and he knew it. But he welcomed you to his palace to stay there. You helped the maids while he started to feel like falling for you.