The Oniwabanshū is a group of ninjas that once served the Tokugawa Shogunate as spies and assassins. After the group was disbanded, most of the former members have become freelancers, taking whatever jobs they can.
- Expy: While their real life counterpart exists, their characterization and primary schtick are pretty much taken wholesale from the group's Rurouni Kenshin incarnation, not unlike Gintoki himself.
Ayame Sarutobi
Voiced by: Yuu Kobayashi (JP), Kazuyuki Okitsu (JP, male), Nicole Bouma (EN, series), Carli Mosier (EN, movie), Carolina Tak (Spain)
A female ninja and former member of the now disbanded Oniwabanshū nicknamed Sa-chan. She meets Gintoki when she falls through his roof during a failed mission and has since become infatuated with him, much to his chagrin. Her feelings for him seem to be encouraged, as she enjoys being put down and threatened by him, due to her blatant masochism.
- Abhorrent Admirer: Sa-chan looks fairly attractive, but Gintoki still finds her abhorrent because of her perverted character and habit of stalking him.
- Action Girl: Having been trained since childhood as a ninja, Sa-chan is an extremely skilled assassin who is especially good at throwing Kunais.
- Assassin Outclassin': She's often shown failing at carrying out her assassinations due to her glasses falling off, leaving her blind.
- Bad Job, Worse Uniform: She works at a "kunoichi cafe", wearing a Highly-Visible Ninja costume between assassination jobs.
- Beware the Silly Ones: Despite her silly and masochistic antics, she is a quite capable fighter when she's not otherwise distracted.
- Big Damn Heroes: Shows up to save Zenzou from being killed by the Kihetai.
- Blind Without 'Em: Her horrible eyesight often leads her into trouble when she loses her glasses, which is made even worse by the fact that she's a ninja.
- Bunny-Ears Lawyer: She's an extremely capable assassin, provided that she has her glasses and Gin is not in her line of sight.
- Crouching Moron, Hidden Badass: Despite her wacky antics, when it's time to get serious she steps up the plate.
- Curtains Match the Window: Purple hair and purple eyes.
- Embarrassing Nickname: "Sarutobi" means "flying monkey", and she's often called just "monkey" by people who don't like her.
- Flanderization: Her wackiness (particularly her bondage kink and her obsession with Gintoki) is turned all the way up and her competence all the way down very shortly after her debut.
- Flechette Storm: Unlike most ninja in the series, she actually prefers throwing only a few kunai at the time, but she's equally capable of throwing a huge barrage of kunai at once.
- Highly-Visible Ninja: While she is a skilled ninja, her poetic declarations and tendency to lose her glasses prove an obstacle for her jobs.
- I Meant to Do That: Obviously the caltrop sticking out of her forehead was thrown there on purpose.
- Improbable Weapon User: She can use natto as a weapon.
- In-Series Nickname: The aforementioned "Sa-chan", which is used more often to address her than her real name.
- In the Name of the Moon: She always recites a poem about the vanity of life before completing a job.
- Knuckle Cracking: Cracks her knuckles when she first appears by simply clenching her fists.
- Lascivious Beauty Mark: Sa-chan has a beauty mark under her right eye and is a masochistic Lovable Sex Maniac who is regularly lusting after Gintoki, often stalking him and begging him for an S&M session. Gintoki isn't pleased.
- Lovable Sex Maniac: She's the most perverted and horniest girl in the series. Her kinky antics are strictly Played for Laughs.
- Mad Love: Gintoki is not interested in her and lets her know this harshly, but she will never stop stalking him as she gladly enjoys the poor treatment and rejection.
- Ms. Fanservice: Pretty much every appearance by her pushes the poor broadcasting regulations to their limits, especially when she shows up in S&M gear or tied up in bondage.
- Named After Somebody Famous: Her family name is a nod to the Sarutobi ninja clan and its most famous head, Sarutobi Sasuke.
- Only Known by Their Nickname: Most people call her by her nickname "Sacchan", making it easy to forget her real name.
- The Peeping Tom: She often hides in the Yorozuya's HQ in order to peep on a naked Gintoki.
- Professional Killer: She works as an assassin. Unfortunately for her, she is seen failing at it more often than not.
- Scarf of Asskicking: She wears a long purple scarf all the time, even in combat.
- Sexy Santa Dress: In the Christmas Episode, Sa-chan's Santa outfit is a form-fitting tube mini dress.
- Single-Target Sexuality: All of her affections and lustful desires are aimed at Gintoki. Other men get the cold shoulder from her.
- Sobriquet Sex Switch: When she's turned into a man in the Dekobokko Arc, she's called Ayao, a male form of her name Ayame.
- Stalker with a Crush: She's often found stalking Gintoki or jumping on him out of nowhere to try stealing a kiss from him.
- Stalking Is Funny if It Is Female After Male: Subverted. All of her antics are strictly Played for Laughs just as much as Kondo is.
- Stock Ninja Weaponry: Carries around some typical ninja gear, including kunai and caltrops.
- Too Kinky to Torture: Throughout the series, there's plenty of scenes of her tied up and/or begging Gin to bang her or spank her. The best example has to be an episode where Gin inexplicably switches bodies with Sadaharu. Sada-Gin then encounters Ayame and lifts his leg on her, in broad daylight, in public, and her reaction is, "YES! DO IT! DO IT NOW!"
- Trademark Favorite Food: Natto, which she even uses as a weapon on occasion.
- Vitriolic Best Buds: Hangs out a lot with Tsukuyo despite the two often bickering with each other.
- Weapon of Mass Destruction: Her glasses become these for a time when Gengai "repairs" them. Hattori even says "Dude, I’m not even entirely sure if we should classify those as eyewear or weapons of mass destruction."
Zenzo Hattori
Voiced by: Keiji Fujiwara, Toshiyuki Morikawa (The Final) (JP). Brent Miller (EN)
A skilled ninja from the Oniwabanshū, acquainted with Ayame. He used to lead the organisation, but with it being disbanded, he takes what jobs he can get. He's a big fan of Weekly Shonen Jump, just like Gintoki—he and Gintoki once fought to the death over the Jump Christmas double issue (which turned to be a double issue of Akamaru Jump). Despite his great skill, he's unfortunate enough to have hemorrhoids. Even more unfortunately, Ayame loves taking advantage of that fact...
- The Ace: Laziness aside, Zenzo is actually the strongest of the Oniwabanshu ninjas. In his first appearance he fought Gintoki to a standstill, has had several One-Man Army feats, and even successfully managed to smuggle the shogun out of his palace after an assassination attempt without anyone realizing.
- Animal Motifs: As a ninja, he compares himself to a cat, while the samurai are dogs. Where dogs are loyal to their owners like the samurai are to their masters, cats are only loyal as long as they are fed in the same way ninjas only serve someone as long as they are paid. Of course, he's a lot more loyal to the Shogun and his friends than his personal philosophy suggests.
- Ass Shove: Poor guy, always getting something stuck up his ass.
- Badass Boast: Makes a boast when he saves Hinowa from Jiraia's mooks.Zenzo: I'll show you how scary a real ninja can be. Pop out your eyes and watch carefully. My moves will be over in an instant. Zenzo Hattori of the Marishiten has come to play!
- Badass Longcoat: He wears a long blue coat as part of his more casual wear. Notable in that he wears it when he saves Hinowa from Jiraia's mooks and single-handedly takes them all down.
- Big Damn Heroes: In the Red Spider arc he shows up to save Hinowa when she is attacked by Jiraia's mooks.
- Brilliant, but Lazy: Similar to Gintoki in combat skill and in obsession with Jump. What's he doing when Jiraia beats Gintoki during the two's first encounter? Laying back on top of a nearby container, reading Jump, claiming he didn't see anything and that he wouldn't get involved, albeit with good reason, citing his father's own clash with Jiraia. Later in the arc he saves Hinowa from a large group of Jiraia's mooks, taking them all down off-screen.
- Butt-Monkey: Despite his great skill, he has literally shitty luck as something always ends up getting stuck in his ass.
- Bystander Syndrome: Despite being nearby during Gintoki and Tsukuyo's first encounter with Jiraia, he stays out of the fight and just reads Jump on top of a container, leaving Gintoki to almost get killed and Tsukuyo to get captured. He does however save Gintoki's life by dragging him out of the water he fell into, before getting him to Yoshiwara for medical attention. He also later saves Hinowa from Jiraia's mooks.
- Combat Pragmatist: As a ninja, Zenzo doesn't care one bit about fighting fairly. Smoke bombs, feints and traps are just the tricks of the trade of his profession.
- Eyes Out of Sight: His eyes are always covered by his hair. In dramatic moments, his blue eyes show themselves from behind the hair.
- Fake Defector: Pretends to defect to the Kiheitai by seemingly assassinating the Shogun, who was actually a Body Double.
- Flechette Storm: Makes his grand entrance to protect Hinowa with an absurdly large amount of thrown kunai.
- Has a Type: In his own words, he's not into pretty women and is more entranced by ugly ones. He was even attracted to the gender-bent Hijikata.
- Historical Domain Character: He is based off Hattori Hanzō, though the most famous persona who held that moniker lived in a different era (then again, the name was a Legacy Character for succeding heads of the Hattori clan). Although his namesake didn't specifically formed the Oniwabanshu in the first place, the historical Hanzo did create the original spy network in Edo and Kyoto that directly served the Shogun and later became the Oniwabanshu. Then there's their Undying Loyalty to their respective Tokugawa lieges.
- In Harm's Way: His former employer Saizo mentions that he feels the most alive when he puts himself in danger. He also gets very excited at the prospect of fighting said former employer and his minions because Okuni had foreseen his death if he did so.
- Intergenerational Friendship: He befriends the clairvoyant little girl Okuni.
- I Was Just Passing Through: His default excuse when he helps the Yorozuya is that he was simply nearby, always claiming that he doesn't want to get involved in any way, shape or form.
- Jerk with a Heart of Gold: He jabs at people and pretends to not care one bit about other people, but will often get personally involved when they are in danger
- Literal Ass-Kicking: Often the victim of this approach from Ayame.
- Mr. Exposition: During the Red Spider Arc he provides most of the information about Jiraia's past, letting the audience know just who he is and what his motives are.
- Ninja: He is a very skilled ninja and is regarded as the closest thing to a leader among them.
- One-Man Army: Singlehandedly defeats Jiraia's large gang of mooks in the Red Spider arc.
- Only in It for the Money: Claims to only have interest in the money he is hired with, but in certain cases he is perfectly willing to do the right thing without being paid for it.
- Pocket Protector: A shojo manga magazine saves his life when he protects Okuni from one of his former employers.
- Professional Killer: Just like Ayame, he works as an assassin.
- Punch-Clock Villain: Briefly serves as an antagonist in the Go-Ninja Arc, but mainly because he just happened to have been hired by the magistrate. Though his earlier encounter with Gintoki where they fought over Jump made their confrontation in the same arc a bit... personal on Zenzo's side.
- Scarf of Asskicking: Like Sa-chan, he also wears a very long scarf all the time, and has no problem fighting while wearing it.
- Stock Ninja Weaponry: He uses a wide variety of typical ninja weaponry in the series, including: Ninjato, kunai, smoke bombs, and flashbangs.
- Straight Man: He's even played straight man to Shinpachi.
- Strange Minds Think Alike: He and Gintoki often comment on how similar they are in tastes and personality.
- Undying Loyalty: Despite his insistence to the contrary, Zenzo is actually extremely loyal and devoted to the Shogun Shigeshige. Part of his loyalty comes from being Childhood Friends with him.
- Volleying Insults: Mostly with Gintoki, whenever a JUMP issue is involved.
Zenzo's Father
Voiced by: Tomomichi Nishimura
Zenzo's father, who died shortly before actually setting foot in the series — though what appears to be his ghost sticks around for a moment to play kick-the-can with Yorozuya. He was the previous leader of the Oniwabanshū, having retired after getting his leg injured while protecting the former Shogun. After retiring, he settled down to teach the next generation of Oniwabanshū; including Ayame Sarutobi and his own son Zenzo.
- Body Double: Acted as one for former Shogun Sadasada, knowing that Jiraia would try to assassinate him.
- Career-Ending Injury: Jiraia injured his legs to such a degree he could no longer work as a ninja.
- Dirty Old Man: According to Zenzo, he sold all of his Jump magazines to buy a lot of porn DVDs.
- Dual Wielding: Wielded two short swords in his confrontation with Jiraia.
- Handicapped Badass: Despite his leg injury forcing him into retirement, he was still a quite capable ninja.
- Manchild: He had a quite childish fascination with the game kick-the-can.
- Ninja: As the leader of the Oniwabanshu, he was a skilled ninja in his own right.
- No Name Given: We never hear his actual name; the most we know for sure is that his family name is Hattori.
- Posthumous Character: Apart from the one instance of his apparent ghost appearing to play kick-the-can with the Yorozuya, he's mostly explored through other characters and in flashbacks.
- Retired Badass: Retired at the time of his death, but seemingly still quite skilled.
- Reverse Grip: Held two short swords reversed in his hands when he faced Jiraia.
Kaoru Waki
Voiced by: Satomi Arai
A fellow member of the disbanded Oniwabanshū, and an acquaintance of both Sa-chan and Zenzo. She works as part of the Shinobi Five, a group of ninjas led by Zenzo which is hired by the magistrate Chintaro Toyama. After the magistrate "kidnaps" Elizabeth, the Shinobi Five clash with the Katsura, Sacchan and the Yorozuya. Apart from working as a ninja, she also has a daytime job at a flower shop.
- Action Girl: She is a capable ninja and fighter, capable of using both kunai and roses as weapons.
- Improbable Weapon User: In her first appearance she uses roses as weapons, throwing them like they were kunai.
- Ninja: Trained as a ninja alongside Zenzo and Sa-chan.
- Petal Power: One of her ninja techniques spreads out rose petals that paralyzes her foes.
- Punch-Clock Villain: Like Zenzo, the main reason she fights Sa-chan and the Yorozuya in her first appearance is because she was hired by the magister that "kidnapped" Elizabeth.
- Something about a Rose: Carries around a rose, and even uses them as weapons.
Gou
Voiced by: Wataru Hatano
Gou is one of the members of the Shinobi Five, a group of ninjas led by Zenzo which is hired by the magistrate Chintaro Toyama. Like his comrades, Gou used to be a member of the now disbanded Oniwabanshū, and was trained by Zenzo's father.
- Butt-Monkey: Gou doesn't have a lot of luck in the two appearances he speaks in. When he is first encountered, he eats Katsura's curry alongside Shuwa and Matsuo, which upsets his stomach and leads to his humiliating defeat. In his second appearance, Sacchan accidentally lands on his crotch and crushes it while he is talking with Zenzo.
- Doppelgänger Spin: After being affected by Katsura's poisoned curry, he uses a ninja technique to make several copies of himself to distract and attack the enemy. Unfortunately, the real him is quite obviously struggling with an upset stomach and he is quickly defeated.
- Groin Attack: Sacchan accidentally lands on his crotch and crushes it during the funeral for Zenzo's father.
- Ninja: He is another ninja trained by Zenzo's father.
- Punch-Clock Villain: Like the rest of the Shinobi Five, he is an enemy the first time he appears because he has been hired by Chintaro Toyama. In later appearances he is actually an ally.
- Scarf of Asskicking: He wears a long red scarf, which comes with the territory as a ninja.
Shuwa
Voiced by: Hisao Egawa
Shuwa is one of the members of the Shinobi Five, a group of ninjas led by Zenzo which is hired by the magistrate Chintaro Toyama. Like his comrades, Shuwa used to be a member of the now disbanded Oniwabanshū.
- Clothing Damage: In the anime, his attempt to use the Doping Technique causes his muscles to grow huge and destroy his shirt. When the muscles then reverse into his legs, he is left with an exposed thin upper body.
- Cool Shades: Always wears a pair of sunglasses, which adds to his tough look.
- Growing Muscles Sequence: After being affected by Katsura's poisoned curry, he attempts to use a ninja technique to increase his already big muscles. In the manga it just causes him to poop, but in the anime it causes his muscles to grow huge and rip his shirt apart, only to then reverse into his legs as he poops, leaving his upper body thin.
- Ninja: Despite his huge muscular appearance, he is a fellow ninja of the Shinobi Five and a former member of the Oniwabanshu.
- Punch-Clock Villain: Like the rest of the Shinobi Five, he is an enemy the first time he appears because he has been hired by Chintaro Toyama. In later appearances he is actually an ally.
- Scarf of Asskicking: He wears a long green scarf, which comes with the territory as a ninja.
Matsuo
Voiced by: Matsuo Matsuo
Matsuo is one of the members of the Shinobi Five, a group of ninjas led by Zenzo which is hired by the magistrate Chintaro Toyama. Like his comrades, Matsuo used to be a member of the now disbanded Oniwabanshū.
- Gonk: He is drawn with an exaggerated and ugly appearance to add to his nerdiness.
- If My Calculations Are Correct: He is able to instantly calculate that the chances of him, Shuwa and Gou being able to counter Katsura and Kagura's curry techniques are 99.8%. When both Gou and Shuwa have been defeated, he calculates that the chances of him being defeated in the next panel or scene is 99.8%, before he is knocked out by Shinpachi.
- Nerd Glasses: Wears a pair of glasses that reinforces his status as the smart and nerdy one of the Shinobi Five.
- Ninja: Despite his rather nerdy appearance, he is a fellow ninja of the Shinobi Five and a former member of the Oniwabanshu.
- Punch-Clock Villain: Like the rest of the Shinobi Five, he is an enemy the first time he appears because he has been hired by Chintaro Toyama. In later appearances he is actually an ally.
- Scarf of Asskicking: He wears a long yellow scarf, which comes with the territory as a ninja.