Nanaumi

Nanaumi is a mysterious masked girl who appeared at the end of chapter 261. She seems to have jolly and playful personality.

The name Nanaumi means "Seven Seas".

Appearance
Nanaumi usually has a grin on her face, showing her blackened teeth. The right side of her hair is white with a small section of black, and colors are opposite to her left. She has a large chest and her clothes mimic the black and white scheme of her hair. Thus far, she has never been seen without her eye mask on.

Personality
Nanaumi is loyal to Hakuryuu and refers to him as "majesty". She seems to like war as she claimed to be excited at the prospect of the incoming war. Anything else about her remains a mystery.

Hakuryuu Ren
Nanaumi is loyal to Hakuryuu as she pledges to fight alongside him.

Trivia

 * Nanaumi's black teeth is a practice of Ohaguro, or dying one's teeth black. This may refer to the ghost story  Ohaguro Bettari, which is about a beautiful looking ghost who pranks men.