In the manga Dandadan, Peeny-Weeny initially appears as an adversarial figure during the Serpo Arc. He had aligned himself with the Serpo group, taking on the role of a mercenary tasked with capturing Okarun. His primary motivation for aiding the Serpo was to secure financial support for his son’s urgent blood transfusion. However, after Seiko intervened and facilitated his son’s recovery, Peeny-Weeny transitioned from an antagonist to a supporting character, eventually becoming an ally to the main cast.

Appearance

In Anime and Original Manga

Belonging to the species known as Mr. Mantis Shrimp’s Race, this character exhibits a striking blend of crustacean and human traits. His head resembles the flat, circular shape of a crab’s shell, while his sturdy, upright physique mirrors that of a muscular human. His skin is muted yellow, and his eyes can shift between the distinct features of a crab and those of a human depending on the situation. Although his wardrobe changes at various points in the series, he consistently sports boxing gloves as a signature accessory. In his human disguise, he takes on the guise of a stern-looking middle-aged man whose serious expression seems permanently etched onto his face, complemented by a hat shaped like his crab-like head.

During his tenure as an operative for the Serpo, Mr. Mantis Shrimp adopted an eccentric, minimalist outfit, consisting only of a tight speedo and a loosely hanging necktie.

In Age-Restricted Manga

Gallery

In Anime and Original Manga

In Age-Restricted Manga

This manga contains content intended for mature audiences. It explores complex themes and may not be suitable for younger readers. The storyline delves into deep character development, intense drama, and emotional narratives. Viewer discretion is advised.

In FanArt

Discover stunning fanart featuring unique interpretations of your favorite characters. From dynamic action scenes to stylish outfits, explore creative artworks that bring them to life.

Personality

Mr. Mantis Shrimp is a multifaceted character with a personality shaped by both his hardships and moral beliefs. When first introduced, he appears as a hot-headed yet chatty combatant, often boasting about his enhanced strength or engaging in verbal banter with his opponents. Despite his aggressive demeanor, he displays a submissive attitude toward his employers, the Serpos, frequently apologizing for his perceived shortcomings and failures.

Much of Mr. Mantis Shrimp’s difficult life stems from being considered weak by the standards of his species. This sense of inadequacy is compounded by personal tragedies, including the loss of his wife to a congenital illness—an illness that their son, Chiquitita, has inherited. Due to Chiquitita’s need for regular blood transfusions, Mr. Mantis Shrimp takes on hazardous jobs to cover the medical expenses. His lack of physical prowess compared to others of his kind has led to social ostracization and mockery from both his peers and employers, causing him deep emotional pain. Consequently, when the Family treated his injuries, offered him a nourishing meal to help him recover, and provided a cow to supply blood for his son’s transfusions, Mr. Mantis Shrimp was deeply moved by their kindness and pledged to support them in any way he could.

Despite his background as a fighter, Mr. Mantis Shrimp considers himself a pacifist at heart. He believes that violence is fundamentally wrong, which is why he refuses to teach Okarun how to throw a proper punch, emphasizing the importance of nonviolence. Nevertheless, his patience has limits, and he admits that if pushed too far, he might resort to fighting. This is evident when he becomes irritable behind the wheel, especially when passengers criticize his poor driving skills.

Adding to his unique character is his quirky verbal tic of ending every sentence with the phrase “deisu” (でいス), a habit that sets him apart and adds a distinct touch to his speech.

Background

Peeny-Weeny’s life on his home planet was marked by both familial love and personal tragedy. He was married and had a son, Chiquitita, with whom he shared a close bond. However, his life took a devastating turn when his wife succumbed to a hereditary illness—a condition that their son also inherited. Faced with the urgent need to secure funds for Chiquitita’s regular blood transfusions, Peeny-Weeny found himself with limited options due to his physical weakness, which made him an outlier among his species. Despite his shortcomings, he had no choice but to take on perilous jobs to support his son’s medical needs. This pursuit of financial stability ultimately led him to work under the Serpo, serving as their hired fighter despite the dangers and moral compromises that came with the role.

Synopsis

Serpo Arc

His miscalculation results in him being kicked into the ceiling, where his head becomes lodged. However, when the Serpo suppress Aira’s abilities using psychokinesis, the Dover Demon seizes the opportunity to punch her with enough force to send her crashing to the ground. He then turns his attention to Takakura, who had attempted to shield Aira, but is swiftly knocked back when Okarun propels himself into the Dover Demon’s chest, aided by Momo’s arrival, which disrupts the Serpo’s psychic hold. Exhausted from the confrontation, the Dover Demon protests as the Serpo forcibly enhance his strength to keep him in the fight. Reinvigorated, he unleashes a barrage of shockwave punches at Okarun and Aira while they remain immobilized by the Serpo’s powers. However, Momo once again intervenes, neutralizing the aliens’ influence and freeing Okarun and Aira to counterattack. Although the Dover Demon holds his ground against Aira—whose enhanced speed prevents her from seeing his attacks—Okarun’s assistance allows Aira to evade the punches, gradually overwhelming the Dover Demon. The battle is abruptly interrupted when the water beneath their feet begins to rise due to Nessie’s sudden appearance.

The Dover Demon is taken aback by Momo’s ingenuity when she uses her psychic abilities to propel Okarun forward while riding on his back, enabling them to rescue Aira from drowning. While reflecting on their clever strategy, the Dover Demon notices a Serpo floating nearby and requests additional time to defeat the humans, only to be startled when the alien’s severed head drifts into view. Recognizing the escalating chaos caused by Nessie, a surviving Serpo fuses itself with both the Dover Demon and Nessie, creating a monstrous hybrid. Following the defeat of the Serpo-Dover Demon-Nessie amalgamation at Okarun’s hands, the Dover Demon, though severely injured, survives the ordeal. Driven by his desperate need to provide for his family, he tracks down Momo and Aira outside the school with the intent to attack. However, weakened from blood loss, he collapses unconscious before he can act. Compassionately, Momo, Aira, and Okarun take the injured alien to Momo’s home to aid in his recovery.

After sharing a meal with the group, he opens up about his struggles to afford the blood transfusions his ailing son requires. Moved by his plight, Okarun offers his genitals as a means of financial assistance, but the Dover Demon declines, determined to uphold his promise of causing no harm. As he prepares to leave, Seiko halts him, remarking that his blood has a familiar scent. Offering him a carton of milk, she observes the Dover Demon’s surprise when he realizes that the milk resembles the blood of his species. Understanding the implications, Seiko arranges for the Dover Demon to obtain a cow from a dairy farmer she knows, ensuring a steady supply of milk for his son’s transfusions. Grateful beyond words, the Dover Demon departs Earth with the cow aboard his spacecraft, vowing never to forget the humans’ generosity.

Sometime later, the Dover Demon discovers that the cow cannot produce milk due to the aquatic environment of his home planet, where a water-like substance permeates the atmosphere. Realizing that sustaining his son’s health is impossible in such conditions, he ultimately decides to relocate to Earth with his son, ensuring a consistent supply of milk essential for the boy’s well-being.

Cursed House Arc

During the Cursed House Arc, the Dover Demon assists Seiko by using his spaceship to help her rendezvous with Momo, Okarun, and Jiji. Upon their arrival, he joins Seiko in battling the Evil Eye, showcasing his combat prowess. During the confrontation, he also guides his son, Chiquitita, in utilizing the Tsuchinoko to extinguish a spreading forest fire. Afterward, the Dover Demon pilots his spaceship to help Momo rescue Okarun, who had become trapped at the bottom of the Tsuchinoko pit.

Later, at the Ayase residence, the Dover Demon and Chiquitita join the group for dinner. During the meal, he informs them of his decision to settle on Earth with his son, planning to live as a farmer. As he prepares to depart, he assures Momo that she can call on him whenever she needs assistance. In response to Momo’s curiosity about his name, he reveals that his real name is Peeny-Weeny. However, Momo and her friends find the name amusing and instead choose to call him “Mr. Mantis Shrimp,” believing it to be a more suitable title.

Evil Eye Arc

While working on his farm, Mr. Mantis Shrimp is approached by Okarun, who seeks his guidance on learning how to throw a punch. Upholding his pacifist principles, Mr. Mantis Shrimp declines, reiterating his belief that violence is wrong.

Later, upon hearing from Okarun that the Ayase house has been destroyed, Mr. Mantis Shrimp and Chiquitita offer their assistance in rebuilding the home. They contact Ludris to obtain nanoskin, a versatile material that allows them to reconstruct the house into an identical replica of the original.

Kaiju Arc

During the Kaiju Arc, Mr. Mantis Shrimp receives a visit from Okarun, Jiji, and Kinta, who seek his help in translating the language of an alien girl named Bamora. He provides them with his translator device, which can only capture fragments of Bamora’s speech. Noting its limitations, Mr. Mantis Shrimp offers to adjust and improve the device when they return, ensuring better communication in future encounters.

Space Globalists Arc

During the Space Globalists Arc, Mr. Mantis Shrimp arrives in time to rescue a critically injured Okarun from a group of suited aliens attempting to capture him. After defeating one of the aliens, he transports both Okarun and the alien back to the Ayase residence to ensure Okarun receives medical care. While traveling through Kamigoe City, he discovers Aira and Jiji, both severely wounded, and brings them to the Ayase home as well. The next day, Mr. Mantis Shrimp expresses relief upon Momo’s safe return and updates her on Okarun’s condition. He observes as Momo confronts Bamora and expels her from the house after discovering her connection to the aliens responsible for the attack. Later, Mr. Mantis Shrimp tends to Momo’s wounds while she converses with Aira and Jiji, who have regained consciousness. When Okarun momentarily awakens upon hearing Momo and Jiji argue, he disconnects his life support to ask them to stop fighting. Noticing the disconnection, Mr. Mantis Shrimp quickly reattaches the device, cautioning them that Okarun cannot recover properly if they continue to quarrel. Momo then gathers the group outside to introduce a Serpo who has allied with them due to the shared threat posed by the alien invaders. Upon hearing the Serpo’s prediction that Earth will be invaded within five days, Momo decides they must undergo intensive training to prepare. Using nanoskin from the reconstructed Ayase house, Mr. Mantis Shrimp helps transform the building into a mobile vehicle, driving the group to a hidden Serpo base. His reckless driving elicits complaints from Momo, Aira, and Jiji, much to his annoyance.

Upon arriving, Mr. Mantis Shrimp inspects the hideout for traps before joining the others in training. Despite his efforts, Aira criticizes his performance, pointing out his flaws alongside those of Momo and Jiji. After the training session, Mr. Mantis Shrimp uses the transformed Ayase house to return home to Chiquitita, ensuring his son’s well-being. The following day, he returns to the training site, waking Momo and Jiji to resume their preparations. Later, he spars with Aira to improve his combat skills while Momo and Jiji practice synchronizing their powers.

With their training complete, Mr. Mantis Shrimp drives the group to the Empty Space, where the Kur are attempting to summon their main forces through a warp gate. Upon arrival, they are ambushed by a group of Kur warriors: Takonoka Ru Patcho, Ta Komeshi, Suda Ko, Ta Kowasa, and the Mantis Exosuit Kur. As Momo advances toward the warp gate to seal it, Mr. Mantis Shrimp, Aira, and Jiji remain behind to hold off the enemies. Mr. Mantis Shrimp engages the Mantis Exosuit Kur while also attacking Ta Kowasa to free Aira from his restraints. Despite his determination, he is overwhelmed by the exosuit’s rapid strikes and energy blades, collapsing from his injuries alongside Aira and Jiji. During this vulnerable moment, the three inadvertently access Bamora’s memories through their Serpo communicators as Momo attempts to heal Bamora’s fatal wound using her powers.

Summoning his remaining strength, Mr. Mantis Shrimp stands and continues to battle the Mantis Exosuit Kur but quickly loses ground. Desperate, he retreats into the nearby river, where his aquatic physiology grants him an advantage. Proclaiming his willingness to fight for the people who have shown him kindness, despite being an alien to Earth, he confronts the Kur with renewed resolve. In response, the Mantis Exosuit Kur shifts its armor into an underwater mode, enhancing its speed and strength. Overwhelmed by the Kur’s rapid assaults and injected with venom, Mr. Mantis Shrimp struggles to break free. Taking advantage of the close proximity, he delivers a powerful punch that damages the exosuit. Capitalizing on the opening, he shifts into his Dover Demon Strong Style Twenty-Four form and delivers a devastating Jet Punch that shatters the Kur’s armor. As the exosuit explodes, Mr. Mantis Shrimp emerges from the water, noting his species’ natural resilience to venom.

Rejoining Aira and Jiji, Mr. Mantis Shrimp, alongside the Evil Eye, reunites with Momo, Okarun, and Bamora to confront the Kur who have breached the warp gate. Following Aira’s orders, Mr. Mantis Shrimp protects Momo and Okarun as they advance toward the gate to close it. Although they succeed in sealing the portal, several Kur ships manage to slip through before it closes. Momo instructs Mr. Mantis Shrimp to assist Aira in holding off the remaining invaders while she and Okarun confront the fleet. The battle concludes with Reiko Kashima using her mirror to trap and eliminate the Kur forces, securing victory for the group.

After the conflict, Mr. Mantis Shrimp drives the mobile Ayase house to retrieve Momo and Okarun, evacuating the city with the rest of the group. At some point after the invasion, he brings Chiquitita to the Ayase residence, where they are welcomed by Seiko, who prepares dinner for the entire group.

Abilities and Powers

Natural Abilities

Physical Prowess

Exceptional Strength: Mr. Mantis Shrimp possesses extraordinary physical power, capable of delivering punches strong enough to shatter solid barriers. Despite his impressive capabilities, he perceives himself as relatively weak compared to others of his species, reflecting his humble and self-critical nature.

Skill Set

Mastery of Boxing: With extensive experience in hand-to-hand combat, Mr. Mantis Shrimp utilizes the principles of boxing to confront his adversaries. His fighting style emphasizes rapid, precise strikes and calculated footwork, allowing him to exploit openings in his opponent’s defense.

Techniques

Forms

Dover Demon Strong Style Twenty-Four
(ドーバーデーモンストロングスタイル24 Dōbādēmon Suto Rongu Sutairu 24)

Augmented Strength

Strengths and Weaknesses

Usage

While transformed, Mr. Mantis Shrimp shifts his combat style from close-range to mid-range attacks. By utilizing his enhanced appendages, he can generate shockwaves with each punch, allowing him to strike opponents from a distance with rapid, powerful blasts of energy. This ability enables him to keep enemies at bay while maintaining offensive pressure.

Techniques

Salary Uppercut (たいぐアパカツ Taigu Apakatsu)

Jet Punch
(ジェットパンチ Jetto Panchi)

Trivia

• During his confrontation with Okarun and Aira, Mr. Mantis Shrimp sings “Chiquitita”, a song originally performed by the Swedish pop group ABBA. In the anime’s localized version, the lyrics were altered, likely due to copyright restrictions.
• The appearance of Mr. Mantis Shrimp’s Dover Demon Strong Style Twenty-Four form bears a strong resemblance to Alien Baltan, a well-known character from the Ultraman series.
• Both the Serpo Energy Drink and the song Mr. Mantis Shrimp sings upon activating his Dover Demon Strong Style Twenty-Four form reference the Regain 24 energy drink commercials, which feature the song “Yuki no Shirushi” by Saburō Tokitō.
• In the manga’s original publication of chapter 23, Mr. Mantis Shrimp’s Dover Demon Strong Style Twenty-Four form was initially illustrated with a pair of sunglasses. However, this design detail was removed shortly after he began his attack on Okarun and Aira, and the tankōbon release no longer features the sunglasses.
• The design of Mr. Mantis Shrimp’s spaceship, which was borrowed from Ludris, closely resembles the Millennium Falcon from Star Wars in the manga. For the anime adaptation, the design was altered, likely to avoid copyright issues.