Kanirante

Kanirante was originally an ordinary human male who transformed into a crab monster after consuming too much crab.

His body is covered in a hard exoskeleton, his arms have turned into powerful claws, and he wears nothing but a single pair of briefs.

He is notable for his bizarre, bubbly laugh, often rendered as “Puku puku puku (laugh)” in spirit, conveying a mocking, giggling tone.

Before the Hero Association existed, he encountered Saitama during Saitama’s job-hunting days and became the trigger for Saitama’s decision to become a professional hero.

Kanirante roamed the city hunting a child who had drawn nipples on his shell with an oil-based marker while he slept.

He had already killed civilians for trivial reasons such as “making fun of him,” demonstrating that he casually murdered humans over petty slights.

Despite often being joked about as one of the weakest monsters in the series, official material later classified him as disaster level Tiger, making him more dangerous than many low-tier monsters.

He appears early in both the manga and the anime, with his defeat playing out almost the same in both versions.

Kanirante has a bulky, humanoid upper body covered in a red crab-like carapace with large claws instead of hands.

His most visually striking features are his protruding eyes, which stick out on stalks from his head and later prove to be his fatal weak point.

He wears only white briefs, creating a ridiculous contrast between his monstrous upper body and his almost comical lower half.

This “briefs-only” look is a deliberate character gag that amplifies his absurdity while still presenting him as a genuine threat.

His personality is cruel, petty, and sadistic.

He hunts a child with intent to kill simply because the kid drew nipples on his shell, and he finds amusement in tormenting those weaker than himself.

Kanirante enjoys mocking his victims, taunting them instead of immediately killing them.

One of his notable lines toward Saitama is along the lines of, “Oh? You’re not going to run away? Puku puku puku (laugh),” highlighting his overconfidence and contempt.

Kanirante is officially classified as disaster level Tiger.

In One-Punch Man terms, this typically indicates a threat capable of causing numerous casualties in a city area if left unchecked.

According to a later fanbook, Kanirante’s combat capability is described as equivalent to five B-Class heroes or one A-Class hero.

This means he is considered more dangerous than the deep sea soldiers with 5–6 meter giant bodies who appear later, at least in raw threat.

Physically, Kanirante’s claws are powerful enough to pierce stone pavement with ease.

He can easily kill ordinary humans with a single strike and has the durability to withstand blows from normal people without issue.

He demonstrates overwhelming superiority over pre-training Saitama, who at that time is just an ordinary man searching for a job.

Kanirante is able to beat Saitama badly, showing that, on paper, he is far beyond what most untrained humans could handle.

While the Hero Association’s disaster level system technically measures the scope of potential damage rather than pure power, Kanirante clearly poses a lethal risk to civilians.

Even if part of his Tiger ranking reflects the number of people he had already killed, the fact that he can effortlessly murder humans confirms how dangerous he truly is.

Encounter with Saitama

Kanirante’s most important narrative role is that he is Saitama’s “origin” opponent.

Before Saitama becomes One-Punch Man, he runs into Kanirante while wearing a business suit, in the middle of job hunting.

Kanirante is in the middle of searching for the child who drew nipples on his shell.

This child is described as having a cleft chin, a notable detail tied into later lore.

When Saitama interferes to protect the boy, Kanirante brutally overpowers him.

Saitama is beaten nearly to death, clearly no match for a disaster-level monster at this early stage of his life.

Despite the brutal beating, Saitama refuses to give up and continues to protect the kid.

This moment becomes the emotional foundation for his later resolution to grow strong enough to defeat any enemy.

Defeat

Kanirante’s fatal weakness is his protruding eyes.

During the struggle, Saitama manages to hook his necktie around one of Kanirante’s eye stalks.

Saitama then yanks with all his strength, ripping out Kanirante’s eye and, effectively, his brain.

The scene is described as extremely gruesome—Kanirante’s “crab brain” is pulled out like crab innards, leading to his instant death.

In the anime adaptation, this death is even more graphic because it is depicted with full color, motion, and sound effects.

Viewers who are sensitive to gore may find this sequence disturbing.

Kanirante is thus killed not by a registered hero but by a normal human who has not yet undergone rigorous training.

From an in-universe perspective, Saitama’s victory over a Tiger-level monster at that time is almost miraculous.

Impact on the Hero Association and Lore

The child Kanirante is trying to kill is strongly implied to be the grandchild of Agoni, the wealthy founder of the Hero Association.

This inference comes from the child’s distinctive cleft chin, matching Agoni’s own, and the later reveal that Agoni’s grandchild was once saved by a mysterious man.

By protecting this child, Saitama indirectly inspires Agoni to create the Hero Association.

That means Kanirante, by threatening the life of Agoni’s grandchild, unintentionally sets off the chain of events that leads to the organized hero system in the series.

In other words, Kanirante’s rampage becomes the catalyst for two key developments:

he pushes Saitama into starting his harsh training, and his actions indirectly inspire the founding of the Hero Association.

From the perspective of fans, this makes Kanirante a surprisingly important figure in the broader One-Punch Man timeline.

Even though he appears only briefly, the consequences of his actions echo throughout the entire series.

Because Kanirante is killed by a pre-hero, pre-training Saitama, many fans initially consider him one of the weakest monsters in the story.

The comedic nature of his design—crab body, briefs, nipple graffiti incident—also contributes to that perception.

However, the later fanbook revelation that he is officially disaster level Tiger, and ranked as strong as several B-Class heroes or one A-Class hero, reshapes how his strength is viewed.

It suggests that early Saitama’s victory was far less trivial than it first appears, highlighting how exceptional Saitama’s resolve and latent potential already were.

Even so, the series and fandom often treat Kanirante with a sense of humor.

His petty motivation, silly appearance, and grotesque demise make him an iconic early-series gag monster.

In the anime, after his death, Kanirante humorously performs the narration for the next episode preview.

This meta joke further cements him as a memorable but comedic presence despite his brutality in-story.

In the anime adaptation of One-Punch Man, Kanirante is voiced by Tokumoto Yasutoshi.

His performance emphasizes Kanirante’s mocking tone and unsettling, bubbly laughter, adding personality to the monster’s short but impactful appearance.