Manga by author Shiozaki Yuji - Status ongoing

It's the 18th century in Naples, Italy. There is a girl named Maria living peacefully in the city, but she is more than she appears. She is like a goddess of death, with a sword that cuts through everything. But what exactly is she? Where has she come from and what cruel destiny awaits her?

From Tokyopop: Sealed in ancient jewels are the spirits of the heroes who tried and failed to unite China in the Three Kingdoms era. These jewels have been scattered throughout Japan, and have the power to draw out the full potential of those who inherit them. However, those owners, known as Toushi, are possessed with an insatiable appetite for battle. Hakufu Sonsaku is one such Toushi. Living in the country, Hakufu's desire to beat something to a pulp goes unfulfilled until her mother tells her to go to Tokyo, where she starts training with other Toushi and sets foot on the path to her destiny.