She is often called Kuu-chan but was referred to as the "Green Girl". She is Minato's second Sekirei. She calls him Onii-chan (Japanese term for 'Older brother'). She has power over plants-to make them grow. She does not like fighting or quarrels and she can be seen stopping them when they start. she said that she wishes to be Minato's wife when she grows up. (Source: Wikipedia)
A black cat who wears a scarf created by the Professor, which allows him to speak. Being theoretically older than both Nano and the Professor when converting cat years to human years, he speaks in a condescending tone towards them and wants to be called "Sakamoto-san", though he often succumbs to his catlike habits. In the last episode, it is revealed that Sakamoto used to be Nakamura's cat and was called "Taisho". Sakamoto does not want to return to Nakamura because she did not take good care of him, even though she had good intentions.
Hakase is an 8-year-old scientist who, despite her outstanding intelligence, often still acts like a child. She loves sharks and snacks, and constantly modifies Nano, whom she created, adding strange and unusual functions such as a roll cake dispensing arm. Nano is usually unaware of these modifications until they are first used. Hakase always refuses to remove the obvious wind-up key from Nano's back on the grounds that it is cute, despite Nano's regular requests. Hakase does not go to school (apparently because she has already graduated) and spends her days playing around in the house instead. Hakase's family is never revealed, though she may be related to the Principal of Tokisadame Highschool since they share a surname. She lives with Nano and Sakamoto. (Source: Nichijou Wikia, edited)
Duval is an enormous man who was originally introduced wearing a medieval looking mask. While standing he shows around two and a half times a normal person height. He has a muscular torso but has skinny arms and legs. Besides his head and shoulders which are covered in armor, he wears an open leather jacket, black pants, cowboy boots, and a long fur cape. Underneath his iron mask, Duval surprisingly looks exactly like Sanji's badly drawn wanted poster. Except for his eyebrow which swirls downward instead of upward like Sanji's, he is an exact duplicate to the drawing. Because of this appearance, he had a lot of trouble with the marines and bounty hunters, and thus had to conceal his face in order to protect himself. While Duval received alot of injuries because of this, his most devastating one is a scar on his back which he states is very painful. Upon confronting Sanji in order to get revenge, Duval got his entire facial structure rearranged by Sanji's kicks. The result of such a crude and violent operation was a complete successful makeover. Due to Sanji's kicks, Duval's entire face had been rearranged into a handsome one completely different from the one he originally had. He absolutely loves it for the benefits it gives. Though turned handsome, Duval however has a hard time winking and thus his eyes would often not wink in unison.
Koushirou is the name of Roronoa Zoro's teacher and Kuina's father. He has his own Dojo near where Zoro grew up and he was the one who trained him. He is typically seen in flashbacks. However, recently, in Chapter 440, he makes a brief appearance when another student of his asked if he was really Roronoa Zoro's teacher. He wished Zoro to go on ahead and fulfill his dream. It is implied he can also cut steel as he follows the method - Swordsman that can cut nothing can also cut steel and anything else they wish, he tries to teach this to Zoro as a child but it isn't until Zoro is 19 before he finally masters it. It is revealed that, at least once in Shimotsuki Village (in a flashback), Koushirou helped the Revolutionaries by providing them food and supplies. He is seen talking with a man with a large face (possibly Emporio Ivankov) after dark, and Monkey D. Dragon even tells his army that they received food by the dojo, while preparing to set sail. First Appearance: Chapter 5; Episode 19 (Source: One Piece Wikia)
Vice-Admiral Tsuru (ã�¤ã‚‹ä¸å°† Tsuru ChÅ«jÅ�) the "Great Tactician" (大å�‚謀 Dai-SanbÅ�) is one of Sengoku's direct subordinates at the base in the Sanctuary of Marie Joie. She is an elderly woman, similar in appearance to Dr. Kureha, but older-looking (and probably younger). She was present for the gathering of the Shichibukai to choose a replacement for Sir Crocodile. First Appearance: Chapter 234; Episode 151 (Source: One Piece Wikia)
Vice-Admiral Momonga (モモンガä¸å°†, Momonga ChÅ«jÅ�) is one of the five Vice-admirals, who lead the Buster Call on Enies Lobby. He eventually returns as the Marine representative meeting with Shichibukai member Boa Hancock near her home island of Amazon Lily. (Source: One Piece Wikia)