Juzo Ogami is a living legend in the Japanese criminal underworld. A hitman without compare, Ogami can kill anyone he pleases if he puts his mind to it. But after a seemingly standard job to clear out a gang, Ogami finds himself in a predicament he never anticipated: a strange wasp sting has turned him into a kid!
Although perplexed by his current condition, he still has bills to pay and offers to keep working to make ends meet. His next assignment? Infiltrate a private middle school and perform an inspection before his boss' daughter enrolls there. Too strapped for cash to refuse, the invincible assassin soon finds himself struggling with school work, his own lack of social skills, and his discomfort with modern technology.
But the most surprising thing of all is how he's starting to enjoy his second childhood.
Kill Blue is an action-comedy manga written by Tadatoshi Fujimaki of Kuroko's Basketball fame, which began serialization in Weekly Shonen Jump in 2023. It follows the legendary hitman Juzo Ogami after he's been physically reverted into the body of a middle schooler. Forced into an environment strange and alien to him, Ogami finds that he likes being a middle schooler more than he thought he would.
Kill Blue contains examples of:
- All Love Is Unrequited: Mai Otohime falls in love with Ogami after the latter saves her from getting hit by a truck. She then devotes all of her energy into trying to seduce him and make him hers. Unfortunately for her, he's completely uninterested as he's a previously married man pushing forty trapped in a middle schooler's body with an ex-wife and daughter.
- Amicable Exes: It's implied that Ogami has been divorced from his ex-wife Eri for some time, as she's once again using her maiden name Wanibuchi. But she doesn't seem to bear any ill will toward him and they're still in regular contact with each other. He even sends the rice balls he made with the Home Ec club to her and their daughter, Kozue. Given how much he thinks about Eri, he clearly still loves her despite their separation.
- Beach Episode: Noren challenges Mai to a surfing contest over who gets to be Ogami's girlfriend. This leads everyone to head to the beach so Noren can trade for said contest (with the rest of the club coming along as a club activity).
- Because I'm Good At It: The only reason why Ogami is still a hitman is because he doesn't know how to do anything else. He was trained to be one since he was an elementary schooler and never even attended middle school.
- Big Eater: Noren is confused when Ogami is on the verge of blowing chunks from eating eight bowls of ramen. She complains that was "only the eighth one" and doesn't suffer from the same Balloon Belly he has. Not only that, she's clearly looking forward to eating more. When the Home Ec club has a ramen-making contest, Noren's creation is loaded with a pile of toppings three or four times taller than the actual bowl. It gets zero points because no one wants to risk their life eating something so laden with salt, sugar, and fat that it makes a meat lover's pizza look like health food.
- Blatant Lies: Due to trying to keep up a facade as an ordinary middle schooler, Ogami repeatedly lies and claims he's never been in a fight before. This is while fending off bullies and showcasing extreme athleticism unbecoming of his apparent background.
- Book Dumb: Justified. Ogami never got to attend school past elementary school because he's been working as a hitman ever since he was child. So he struggles to keep in school on his own once more advanced subjects are brought up and he's too prideful to ask his teachers for aid. It's not until he gets help from his classmate, Ryo Shiraishi, that his grades improve.
- Boyfriend Bluff: Because of all the people vying for her hand for the sake of her father's company, Noren impulsively declares that she's dating Ogami in an attempt to fend off her suitors. He's clearly alarmed at being volunteered like this, but decides to go along with the ruse for the sake of keeping all the other guys away from her due to her reminding him of his own similarly-aged daughter and out of appreciation for her ramen. Unfortunately, this doesn't dissuade said suitors much at all, as they now focus on trying to bully Ogami or take the pen symbolizing Ogami's apparent relationship with Noren through competitions.
- Broken Ace: Ogami is a peerless hitman with inhuman aim and the ability to wipe out entire gangs on his lonesome. He's also completely friendless, divorced (albeit Amicable Exes with his ex-wife), and living alone in an apartment while eating nothing but ramen. He takes no pleasure in his infamy and calls his life pathetic while wondering what he could have done better. In addition, his lifestyle deprived him of an education beyond elementary school, leaving him unable to be anything other than a hitman. This is actually why Ogami grows to like being a middle school student because it gives him the chance to learn and experience things he was never able to during his actual childhood.
- Charles Atlas Superpower: Ogami is capable of blatantly superhuman feats through nothing but his own training and experience. He hops up a signal tower in an instant to use as a vantage point and throw chalk hard enough to instantly burst into a cloud of dust upon hitting a wall. But he notes that his strength has diminished due to having the body of a child, hence why he's unable to knock out the panda pervert in the first chapter with one punch to the gut.
- Commonality Connection: Ogami and Noren grow closer when she learns he shares her appreciation for her uncle's ramen. This gets Noren to open up about her love for ramen and her desire to inherit her uncle's shop without being tied down by her family's pharmaceutical company. The same conversation gets Ogami to look at her not just as someone to approach to help solve his predicament but also someone who likes ramen even more than he does.
- Cursed with Awesome: As Ogami gets used to his predicament, he finds being a middle schooler more enjoyable and fulfilling than his old life as a hitman ever was, wishing that these days could go on forever. Ogami also doesn't mind not being as strong as he was as an adult if it means lacking of aches and pains from being middle-aged.
- Deliberate Values Dissonance: As a nearly 40-year-old man who is largely a social recluse, Ogami's values are outdated and old-fashioned by modern standards. He initially brushes off the idea of men keeping house as a woman's job and uses some possessive language while trying to defend Noren. But he's called out for this and made to change his ways as part of his attempts to fit in.
- Does Not Like Men: Noren developed a hatred of most men because of how they make passes at her solely to inherit her family's pharmaceuticals company. The way they leer at her while clearly fantasizing about how to exploit her disgusts her. Ogami is one of the first boys her (apparent) age she can feel comfortable around because he clearly doesn't see her that way (and has no attraction to her at all as a man pushing forty with an ex-wife and child).
- Eating the Eye Candy: When Tenma shows up to the beach shirtless, passerby instantly comment on his chiseled, athletic physique and try hitting on him. He has absolutely no interest in them though."Now that I get a better look at him... Damn, he's hot! I mean, that musculature is sick! A prime physical specimen!"
- Fountain of Youth: The plot begins when Ogami is stung by a wasp created by a genetic engineering company that reverts him to a twelve or thriteen-year-old physically.
- The Gift:
- Tenma is naturally tall, hard-working, an innately talented at any sports he puts his mind into. He's considered a "unicorn" for his extreme athletic talent and can compete with assassins who have trained themselves to the point of having a Charles Atlas Superpower.
- Mai Otohime is an aquatic athlete who is similarly talented unicorn in marine sports. Scuba diving, fishing, surfing, yachting, if there's a sport that takes place on water, she's amazing at it. She's also a gifted sailor, marine cartographer, and marine biologist, leading others to call her the "incarnation of the sea".
- Goggles Do Something Unusual: As part of his middle schooler disguise, Ogami wears a pair of glasses with hidden cameras and a two-way comms function so Nekota can see what he sees to act as his Mission Control.
- Heroic Self-Deprecation: Ogami tells a gangster that anyone who doesn't know how to treat a lady is trash. Given Ogami's divorce and calling himself pathetic for not being a better husband, this is also a clear jab at himself.
- Hitman with a Heart: Ogami may be a hitman, but he refuses to take jobs that involve killing women, children, or innocent civilians. Off the job, he's typically nice despite his gruff attitude.
- Improbable Aiming Skills: One of Ogami's defining skills is his incredible precision with a gun. He's able to shoot a tracker onto a speeding car from atop a transmission tower with ease. Later on, he defends innocent bystanders caught in his shoot out with another assassin by shooting his opponent's bullets out of the air. He then tops this by shooting nearly straight up into the air so the bullets will arc down and hit his intended targets anyways due to the pull of gravity. The absurdity of his feats is lampshaded repeatedly and called inhuman, with even Ogami admitting that he can only get his "shooting up into the air" trick to work about 70% of the time.
- In-Series Nickname: Ogami grows to respect Chisato immensely, calling her "capo", as in "caporegime" (a Mafia title roughly equivalent to captain) on instinct, for being the head of the Home Economics Club. He also calls Ryo "Master" for helping him with his studies.
- Like Brother and Sister: Noren believes she may be falling in love with Ogami for real because of how comfortable she is around him unlike nearly every other man she's met. But talking with Tenma helps her come to the conclusion that her feelings may be closer to fraternal than romantic. Hearing this gives Ogami the idea to nip any potential romance in the bud by spinning a story of how he's just as uncomfortable around girls as she is with boys, letting her conclude that it really is better if they're just friends. Lampshaded by Nekota, who says they double friend-zoned each other.
- Living MacGuffin: Noren Mitsuoka is the only heir to her family's pharmaceutical company, and her father declared that whoever marries her will inherit the company from him. This has led to many unsavory figures trying to win her hand in marriage for the sake of taking the business and the resulting miracle drugs it's developing, such as the wasp that reverted Ogami to a child.
- Locked into Strangeness: Although Ogami is physically twelve or thirteen years old, half of his hair is still as gray as it was when he was still middle-aged. This is the only physical clue that he's not just a middle schooler, as he has no real distinguishing features otherwise.
- Lonely at the Top: Discussed. Tenma's overwhelming athletic talent means that he crushes the competition on average. When his Childhood Friend asks him if he'll be lonely at the top of the sports world, Tenma replies that he wants to be lonely at the top, a legend no one can possibly match. He doesn't even want a Worthy Opponent, he's just in it to enshrine his name in history.
- Men Can't Keep House: Ogami's place is a mess because he hasn't called his housekeeper over for a while and he doesn't plan on changing now. According to him, cleaning is a job for women. Nekota calls him out on how outdated his values are. Ogami starts coming around to the idea of cooking and cleaning for himself with the Home Ec club and hearing how much his daughter and ex-wife enjoyed the rice balls he made for them.
- Mission Control: Ogami's partner/protege, Nekota, supports Ogami from behind a computer. He's able to advise Ogami and send him information via the cameras and comm systems hidden in Ogami's glasses. He also sends Ogami his gun in a pinch via a drone.
- Mixed Ancestry Is Attractive: Noren Mitsuoka is described as tall and beautiful "like a model", and is constantly getting leered on by boys and adult men alike, resulting in her distaste for the opposite sex. She ascribes her good looks to her Canadian mother.
- Muscles Are Meaningless: Ogami is average in height and build in his middle schooler body. But he still showcases extreme Charles Atlas Superpower, such as hopping up a transmission tower with ease or keeping up with the much taller and more muscular super athlete Tenma.
- Mundane Luxury: Having never gotten an education past elementary school, Ogami is blown away by the breadth of topics he's learning in middle school. By the end of his first day, he's sobbing Tears of Joy because of how much fun he's having as a student compared to his dead-end job as an assassin.
- My Grandson, Myself: Ogami's was physically reverted to a middle school by a strange wasp sting, but his skills remain untouched. When another assassin recognizes Ogami's impeccable marksmanship and threatens to out him, Ogami quickly spins a story of being his own love child as the reason why he's so accurate. His opponent buys it and starts to share his own Dark and Troubled Past before deciding it isn't worth it.
- My Sister Is Off-Limits: The normally nice and easygoing Ryo is enraged when Tenma starts making moves on Chisato. Ryo instantly pulls out his shinai and declares his intent to slice Tenma to ribbons for asking out Chisato. Even Ogami, a hardened assassin, is terrified by how quickly Ryo's attitude changes.
- Never Hurt an Innocent: Despite his reputation as a hitman who will kill anyone for the right price, Ogami makes a point of restricting his targets to "iredeemables" like murderous gangsters. Even after being turned into a kid, he doesn't do anything permanently harmful to the troublemakers he runs into.
- No Social Skills: Tenma admits he's always struggled with being able to read the room and people accurately, resulting in him constantly offending people even when it's not his intention. He's well aware of this and it's why he wants Chisato to help him better understand people
- Papa Wolf: One of the reasons why Ogami continues to act as boyfriend for Noren is because she's the same age as his daughter, Kozue. The idea of all these guys trying to exploit her inflames Ogami's fatherly instincts, leaving him just as disgusted as she is at her situation and instilling in him a desire to protect her.
- Perpetual Poverty: Despite his skills as an assassin, Ogami is perpetually broke between paying child support, his mortgage, and his car loan. He also runs up other bills too, like constantly eating out because he can't be bothered to cook and hiring a housekeeper instead of doing his own chores.
- Pop-Cultural Osmosis Failure: After scarfing down eight bowls of ramen while trying to help Noren with a ramen-making contest, Ogami suffers a Balloon Belly and compares himself to Cell when he's about to explode. Given that the scene was aired on TV in 1993, Noren misses the reference completely as she wouldn't have been born at the time of airing.
- Porn Stash: Invoked. Ogami realizes that Noren might be developing feelings for him and has Nekota send him a porno in hopes that he can make Noren disgusted enough to quash those feelings that are never going to be requited. Nekota tries to dissuade him, reasoning that disgust will quickly turn to hatred and Ogami's and Noren's relationship will never be the same.
- Rescue Romance: Mai Otohime falls in love with Ogami after he saves her from being run over by a truck.
- Sacrificed Basic Skill for Awesome Training:
- Ogami is an inhumanly good marksman, a skilled hand-to-hand combatant, and an all-around unstoppable hitman. But his training deprived him of a normal childhood and stunted his social skills. He has no hobbies outside of work and struggles to fit in when forced to attend school.
- Tenma has The Gift when it comes to soccer, baseball, and basketball with the height, physique, and work ethic to match. But he's completely apathetic to his studies and he admits to having No Social Skills. He struggles to read a room and has no filter for his thoughts.
- Shout-Out:
- After suffering from a Balloon Belly from eating eight bowls of ramen with Noren, Ogami complains that he feels like he's about to explode Cell. Meanwhile, the shadow of the self-destructing Cell can be seen behind Ogami.
- When he gets temporarily turned back to his adult self, he's forced to use a voice modulator sticker to avoid rousing suspicions. Nekota comments that Ogami won't like the design, prompting the latter to comment it's fine as long as it isn't a bowtie.
- Single-Target Sexuality: Tenma falls for Chisato after she dresses his injuries from his match with Ogami and hearing her thoughts about looking out for others. He immediately asks her out the day after and tells her that he wants to spend the rest of his life with her despite being completely clueless to the advances of others.
- Spirited Competitor: Tenma is driven to become a "triple threat" super athlete excelling in baseball, soccer, and basketball because he simply loves sports so much. While he'd love to crush every game 100-0, he gets even more excited when there's someone who can keep up with him enough to make the game interesting.
- Split Personality: Mai Otohime has two personalities: one where she's a meek, fair-skinned schoolgirl and one where she's a rowdy elite marine athlete who's also lovestruck for Ogami. She switches between them by taking a nap, with the change being so drastic that even her figure changes in the switch.
- Stock Shōnen Hero: Tenma Tendo is a brawny, Hot-Blooded genius at sports who wants To Be a Master in baseball, soccer, and basketball. He hates studying to a fault, basks in the limelight, and tackles every challenge with a smile. He's also brave, hardworking, and extremely upfront with all of his thoughts and feelings.
- Technologically Blind Elders: Ogami is a middle-aged man and struggles to use his smartphone for more than basic calling. After being added to a group chat, he panics at the rapid-fire texts he receives until Nekota informs him that he can just mute the notifications.
- Thou Shalt Not Kill: Downplayed. Ogami is an assassin, so killing is his specialty. But he doesn't really like to do it when he isn't getting paid for it. So he shoots the gangsters who kidnapped Mitsuoka with rubber bullets.
- Trademark Favorite Food: Ogami has a taste for ramen, as it's cheap, filling, and delicious, making it both practical and enjoyable for him. Him walking into Noren's uncle's ramen shop is what leads the two of them to start bonding, as she loves ramen even more than he does
- When I Was Your Age...: Ogami still reflexively talks like an old man when he's agitated. For instance, when he's playing soccer against Tenma, Ogami thanks him for getting him fired up and desperate to win in a way he hasn't felt since "back in the day". Tenma is baffled that Ogami is talking like a spent old man when Ogami is supposed to have just entered middle school.
- Wholesome Crossdresser: Nekota arrives as Ogami's mother when it comes time for parent-teacher conferences. While they look nothing alike, Nekota seamlessly passes as a woman (concerns about Nekota hitting Ogami aside).
- Willfully Weak:
- Because he needs to maintain his cover as an ordinary middle-school student, Ogami is forced to run away from bullies he can easily beat up because he can't risk expulsion and losing his paycheck for the job.
- Tenma tends to hold back when playing at first because he loves sports so much that he doesn't want the other team to throw in the towel immediately. He takes off the proverbial kiddie gloves when it's clear that Ogami can compete with him.
- Worf Had the Flu: Invoked. Ogami gets so worked up that he actually manages to keep up with Tenma, a known super athlete, in a soccer match. This gets Ogami mobbed by the sports clubs after the game, threatening to put an end to Ogami's dream of a quiet middle school life. After hearing about this, Tenma offers to tell the press that he wasn't at his best due to an injury, thus making Ogami's performance less impressive by comparison.
- Working with the Ex: Ogami's ex-wife Eri happens to also be the chief scientist of the Z.O.O, the assassin syndicate he works for.
