The Titular Heroine
The lovely protagonist of the series who fights for love and justice... all while completely exposing her naked figure to the world! Everyone knows her body, but nobody knows her face! Wherever there is injustice (or pervy teachers) she'll be there to defend the weak and deal out righteous punishment to any evildoer who gets in her way!
- Action Girl: Don't let the silly name and costume fool you, she's the star of the show for a reason! From evil BDSM nazi dominatrix baronesses to cloth-cutting rouge samurai mercenaries she's fought and defeated numerous dangerous opponents using nothing but her wits, skill and shameless exhibitionism.
- Badass Normal: She mostly just relies on her nunchaku, martial arts and pure unrestrained sex appeal to win fights. Considering that some of her opponents included a rouge samurai and a combat android girl this is pretty impressive.
- Collective Identity:It's gradually revealed over the course of the manga that there are multiple women acting as Kekko Kamen.
- Combat Pragmatist: The reason she "hides her face but not her body" is to distract her opponents and hitting them while they're distracted by her sex appeal. And if they aren't distracted, then she gets dirty.
- Even the Girls Want Her: The female students admiration for her evidently is more than just gratitude for her acts of heroism, as a lot of them outright admit she's sexy.
- Ms. Fanservice: One of the biggest ever in all of fiction. What else can be said about a girl who charges into battle fully nude save for a mask and uses her own nether regions for her finishing move?
- Stripperiffic: Taken to an absurd extreme. Aside from a stylish mask and a few accessories she rushes into battle completely nude.
Sparta Academy Faculty
Head Staff
The cruel, evil and highly perverted principal of Sparta Academy and Kekko Kamen's main archnemesis. He runs the isolated school with an iron fist and dishes out extremely harsh punishments to any students who get poor grades or interfere with his diabolical schemes. He also employees a select group of enforcers known as the "Punishment Councilors" to go after any student who especially displeases him.
- Beware the Silly Ones: As ridiculous as his name and choice of attire are he is still the headmaster of the school and commands quite a lot of power within its walls. He can even be a surprisingly dangerous and clever foe himself when he wants to be.
- Big Bad: He runs the school where the story takes place and takes special delight in tormenting the students with his perverted and humiliating antics. He's also responsible for bringing in each of the elite "Punishment Councilors" that Kekko Kamen must fight in each episode.
- Cool Mask: As ridiculous, perverted, and goofy he is, the mask he wears is pretty stylish looking.
- The Cuckoolander Was Right: He states that he hired Shuwarutsu Negataro because since Kekko Kamen is a lady with big breasts, she'll find his big muscles and handsome face irresistible and he'll immobilize her with his sexiness. Surprisingly, he turns out to be completely right once Shuwarutsu starts flexing and posing sensually at her, rendering her paralyzed due to how sexy she finds Shuwarutsu.
- In the manga he quickly deduces that more than one people hide behind Kekko Kamen's mask, and once in a while he tries to prove it no matter how many times he's proven wrong. He's ultimately proven right, and the only reason he couldn't prove it is that he only suspected four out of six of Kekko Kamen's identities.
- Dirty Old Man: He's heavily implied to be middle-aged, at the least, and has an obsession with all things lewd and innapropriate.
- Expy: He's a parody of Satan's Claw from Moonlight Mask.
- Malevolent Masked Man: He's never seen without his mask.
- Not-So-Well-Intentioned Extremist: Despite the inhumane, extreme methods employed at Sparta Academy and the sadistic assholes of faculty that work there, the students that do graduate end up becoming extremely successful in their lives. Despite this, a lot of his behavior, namely his perverted ways and willingness to bribe his own students show that he's partially using Sparta Academy for his own gain.
- Smarter Than They Look: Despite wearing a silly outfit and behaving like a ridiculous pervert, he's actually quite clever, as he comes up with cunning plans, like manipulating the students that Kekko Kamen is supposed to be protecting to turn them against her to try and defeat her. His suspicions that there are multiple women who play the role of Kekko Kamen and that they're both in the faculty and the student body are all also correct.
- Villainous Harlequin: He dresses up like one due to his poofy hat and grinning mask.
Big Toenail of Satan's right hand man and accomplice who is just as sadistic and perverted as his boss. Teacher Ben may not seem like much but he has caused his own fair share of misery to the students of Sparta Academy by himself and can become a surprisingly credible threat when working together with his boss.
- Adaptational Heroism: Downplayed. He was a maniac who wanted to dissect Mayumi's cat as well as Mayumi herself, but he's portrayed as being sound of mind, although still a sadistic asshole like a good 99% of the teachers in Spartan Academy.
- Ascended Extra: He was a one shot villain in the original manga, but he's portrayed as The Dragon for Satan's Toenail in the OVA.
- Ax-Crazy: At least in the manga. He's clearly out of touch with reality, as he tries to dissect Mayumi Takahashi's cat, and, when she begs him to not do it and says that her cat is her friend, he immediately assumes that she, too, must be a cat, as in his own twisted logic, only cats can be friends with cats, and immediately decided to dissect her instead.
- The Dragon: He's Big Toenail of Satan's second in command and is often shown assisting his master in whatever evil plans he is carrying out in the episode.
- Shout-Out: He's based off of the eponymous protagonist of the medical drama Ben Casey.
Punishment Councilors
A vicious nazi BDSM dominatrix (yes, really) from Auschwitz Academy who is brought in to discipline the students and help lure out Kekko Kamen. After a brief battle she is completely dominated by the masked heroine and is left lying on the ground in a heap of ecstacy. (In the shape of a swastika, naturally.)
- The Baroness: A cruel and sadistic minion of the villainous Big Toenail of Satan... and did we mention she's also a literal nazi dominatrix on top of that?
- Those Wacky Nazis: Her gimmick. She even has mooks in the form of Nazi soldier cosplayers, complete with antiquated rifles.
A buff gay man who is picked by Big Toenail of Satan to exploit one of Kekko Kamen's biggest weaknesses... a sculpted muscular physique that drives her crazy with lust. Though he was immune to Kekko's feminine charms he was nonetheless beaten when she put on a blindfold to hide him from her sight and then nailed him with an "Open Thigh Charge" to finish him off.
- Chick Magnet: His good looks and big muscles make him this, as all the female students are practically drooling over how sexy he is, in spite of him being gay.
- Distaff Counterpart: He's essentially a male version of our titular heroine herself, thanks to his gimmick of distracting people with his handsome face and big muscles.
- Distracted by the Sexy: He weaponizes this against Kekko Kamen, because she finds his handsome face and big muscles to be incredibly sexy to the point where she ends up being the one to be paralyzed by lust.
- Mr. Fanservice: He's a handsome, heavily muscled man whose "power" is that he strips to nothing but a pair of trunks and tights that are very flattering to his figure to distract his opponents with his raw sex appeal.
- Straight Gay: He's gay, yes, but he lacks the flamboyancy to qualify as Macho Camp, as well as the overwhelming machismo to classify as Manly Gay.
- Walking Shirtless Scene: Though he occasionally wears a shirt when serving as a P.E. teacher he's always quick to remove it in battle due to how his abilities work.
An android programmed by Big Toenail of Satan and Teacher Ben to infiltrate the student body and improve their test scores. After befriending Mayumi she attempts to fix her terrible grades but when the poor girl fails to get a single right answer on a paper she reveals her true form and attacks her with electric tentacles. She is destroyed by Kekko Kamen successfully deducing the location of her off switch (her nipple) and shutting her down permanently.
- Combat Tentacles: She has these.
- Robot Girl: She's secretly an android created by Satan's Toenail and Teacher Ben to observe and punish the students for failing grades.
- Shock and Awe: Her tentacles also have the ability to electrify things.
- Weaksauce Weakness: She's a powerful combat android that actually had Kekko Kamen on the ropes for a bit... until the heroine realized that one of her nipples was an off switch.
A rouge ronin who is hired by Big Toenail of Satan to hunt down and defeat Kekko Kamen. To lure her out he stalks the female students with poor performances and delivers a devastating combo attack consisting of him cutting their clothes to shreds and then photographing their nude bodies with his camera. Despite coming up with a counter to Kekko Kamen's initial finishing move she figures out a way to bypass his defenses and sends him flying.
- Line-of-Sight Name: How he comes up with a name after realizing that he doesn't have one. He looks down at the ground and sees a puddle, and immediately declares that his name is Mizutamari Tsuyokaro.
- Unfortunate Names: He doesn't even have a name, and the name he makes up for himself is incredibly lame, as it literally means Puddle Strongman.
Sparta Academy Students
An extremely unlucky female student who is often targeted by the Big Toenail of Satan both because of her awful grades and because she makes good bait to lure Kekko Kamen out. As such, she ends up playing the role of distressed damsel in each episode, forcing the masked heroine to brave the minions of the "Punishment Council" to save her from whatever nasty enforcer Big Toenail has employed that week.
- Adaptational Dumbass: She's portrayed as a genuinely bad student in the OVA, rather than having bad luck and actively being singled out by the Big Toenail of Satan.
- Book Dumb: In the OVA she's a legitimately poor student while the original manga typically had her be more of a victim of circumstance and just plain bad luck.
- Butt-Monkey: Almost nothing ever goes her way. In just the first episode of the OVA she's tied up, stripped nude, tortured and humiliated in front of the entire student body. If not for Kekko Kamen showing up from time to time the poor girl would probably never catch a break.
