This article is about a/an rider in Kamen Rider W.
For the A. R. world version, see Sokichi Narumi (A.R. World).
"Now, count up...your sins/crimes!"
―Skull's pre-battle catchphrase[src]
Sokichi Narumi (鳴海 荘吉 Narumi Sōkichi) was Kamen Rider Skull (仮面ライダースカル Kamen Raidā Sukaru), he was also Shotaro's mentor (whom he refers to as "boss"), Akiko's father, and founder of the Narumi Detective Agency in Futo City.

Character History

Becoming Kamen Rider Skull

While working as a private investigator, he was partnered with a man, similar to his protege Shotaro Hidari's partner Philip, named Seiichiro Matsui (nicknamed Matsu) and had the personal policy of never getting clients in danger. He also provided his childhood friend Fumine Sonozaki (now Shroud) refuge after she was forced to leave her family and take up her new identity. Sokichi gets a job to protect a friend of his and Matsu's, Melissa, who is a singer. She receives a letter from a man calling himself "the Spider Man" (クモ男 Kumo Otoko) , which tells her to sing a specific song. The letter goes on to say that the Spider Man will rate the song on a scale of 1-100 and for every point below 100, he will kill an audience member. After confronting Melissa's agent at the concert, the Spider Man, revealed to actually be the Spider Dopant, attacks the crowd. He gives Melissa 100 points, and no one would be killed. However, Sokichi takes the opportunity to attack the Dopant armed with only the Stag Phone. A young Shotaro is in the audience, and comments in awe of how cool Sokichi is. After returning home, Sokichi talks to Shroud, who is working on the secret hangar (which then housed the SkullGarry). Shroud offers him the Skull Memory and Lost Driver when he asked her for suggestions on how to fight the Dopants. He rejected the gift outright due to wanting to keep his humanity intact.

Sokichi investigates further into Melissa's agent, and at the Yaguchi Talent Agency encounters the Spider Dopant again, along with the Bat Dopant and many Masquerade Dopants. Sokichi is almost killed by the Spider Dopant, but at the last second, Shroud arrives and tosses him the Lost Driver, the Skull Memory already inserted. The Driver attaches itself to Sokichi's waist, and he transforms into Skull Crystal against his will. Shroud notes that Skull is still incomplete, but Sokichi resumes his fight with the Spider Dopant and his horde of Masquerade Dopants nonetheless. During the fight, an energy sphere begins emerging from Skull's armor, but its appearance distracts Sokichi and gives the Dopants the upper hand. After receiving a call on the Stag Phone from Akiko, Sokichi gets the motivation to fight off the two Dopants. After seeing Yaguchi assumed to be the Spider Dopant, he was supplying Museum with test subjects, but killed by one of the Spider Bombs. Sokichi determines that the Spider Dopant's true identity is Matsu, thanks to noticing a quirk in his handwriting appear in a message the Dopant webbed on a wall. Sokichi confronts Matsu and learns his whole reason for becoming the Spider Dopant was because he was madly in love with Melissa, but she loved Sokichi. He implanted a Spider Bomb in Melissa, and tells Sokichi that the bombs activate when their host touches the one they love most. After infecting not only Sokichi, but most of Futo as well, Matsu departs as Spider Bombs explode all over Futo.

Sokichi runs after Matsu but is intercepted by the Gaia Memory Dealer, Eren Komori, who transforms into the Bat Dopant. Sokichi transforms into the complete Kamen Rider Skull, and fights the Bat Dopant. Instead of a Memory Break, Sokichi leaves Komori to die by leaving her trapped under a leaking gas tanker truck, which then explodes. He then goes to fight Matsu, and begins counting his sins: how he didn't see the darkness in Matsu's heart, how he hesitated to fight Matsu when the time came, and because of these sins, Futo suffered. He then tells Matsu to count his own sins, and the two fight once again. Sokichi ends the fight with his Maximum Drive, but because of the Memory's side effects, Matsu dies.

Despite his crimes, Sokichi still called Matsu his partner. Since the incident, Sokichi took the motto "Now, count your sins!" to heart so that nothing similar ever happens again. Furthermore, the Spider Bomb implanted in Sokichi did not fade after the Spider Memory's destruction. Knowing what would happen if he ever reunites with his beloved daughter again, Sokichi isolates himself from Akiko to ensure his daughter's safety. After this, Sokichi became involved in investigating cases involving Dopants that the police force could not handle, including the armored car robberies performed by the "Beastman".

Begins Night

Eventually taking Shotaro Hidari as his protege, Sokichi taught Shotaro about being a detective as well as acting somewhat like a father figure to him. Around Christmas, after scolding Shotaro for wearing his hat without permission as well as telling Shotaro to not wear it until his approval, Sokichi agrees to help Shroud stop the Museum by infiltrating a research facility known as the Gaia Tower with Shotaro in order to find the young man at its center. However, Sokichi is intercepted by several henchmen of Museum. Telling Shotaro to stay put with the suitcase he brought with them (which contained the Double Driver and all of Double's Memories), he defeats them with little effort. However, the men become Masquerade Dopants, and the Taboo Dopant appears. Having no choice, Sokichi transforms into Skull, much to Shotaro's awe. After dealing with the Dopants, Sokichi finds that Shotaro inadvertently sent the young man they were looking for to the crystal chamber used to create Memories at the top of the tower. Sokichi touches the chamber upon their arrival, and enters the Gaia Library, something the boy says only an impressive man could do. Sokichi offers him freedom to find atonement for his part in the creation of the Gaia Memories, naming him Philip after his favorite fictional character, Philip Marlowe. After Sokichi frees Philip from the Gaia Tower and begins to take both him and Shotaro out of the building, he is shot by several armed guards. As he dies, he gives his white fedora to Shotaro and asks Shotaro to become a man worthy of wearing it. It was after the Gaia Tower fell into ruins that Shotaro and Philip, spurred by his advice to continue in his place as Double, learn that Sokichi's body is nowhere to be found. Even though Sokichi seemingly died, his will as a protector of Futo continues to live through Double as noted by Philip.

Kamen Rider × Kamen Rider W & Decade: Movie War 2010

In Begins Night, Sokichi Narumi and Kamen Rider Skull are among the identities taken by the Dummy Dopant while pretending to be the Death Dopant in a scheme to assume the identities of Fuuto's upper class members, using Sokichi's form to drive Shotaro off from the case before he realizes the truth. However, Shotaro finally overcomes this and Double ultimately defeats the impostor Kamen Rider Skull. After the case is concluded in Movie War 2010, Tsukasa Kadoya uses a Kamen Rider Skull card he has acquired to summon an iteration of Sokichi Narumi from an alternate dimension, giving Shotaro closure. This Sokichi doesn't seem to know Shotaro, but regardless, praises him. He then takes his leave after telling Shotaro the way he wore his hat was proof of being a full man as well as telling him that they should meet again.

Kamen Rider W Forever: A to Z/The Gaia Memories of Fate


Kamen Rider Skull's final appearance is in Kamen Rider W Forever: A to Z/The Gaia Memories of Fate, where the ghost of Sokichi who transformed into Skull gives Shotaro his Lost Driver as well as helped him realize Philip's feelings before fading away as he takes his leave, enabling Shotaro to transform into Kamen Rider Joker. The Skull Memory is also one of the 26 T2 Gaia Memories in the film.

Kamen Rider × Kamen Rider OOO & W Featuring Skull: Movie War Core

Kamen Rider X Kamen Rider OOO & W Feat.Skull Movie War CORE Director's Cut-19-13-54-

During Akiko's wedding, Sokichi appears for the final time in spirit, walking with his daughter down the aisle and entrusting her to Ryu.

Chou Super Hero Taisen

More Sentai and Riders 3

Video Game appearances

Kamen Rider: Battride War

Skull (Battride War)

Skull in Battride War.

Kamen Rider Skull appears in the video game Kamen Rider: Battride War.

Kamen Rider: Battride War genesis


Kamen Rider Skull in battrider war Genesis

Kamen Rider Skull appears in the video game as a tag partner in Kamen Rider: Battride War.

Kamen Rider Buttobasoul


Kamen Rider Skull Medal

Kamen Rider Skull is a playable character in Kamen Rider Buttobasoul.


Kamen Rider Battle Rush

Kamen Rider Skull appears as a playable and support character in the video game Kamen Rider Battle Rush using Rider Shot.

Other Game appearances

Battle Spirits

Card g04

Kamen Rider Skull Battle Spirits card

Sokichi Narumi as Kamen Rider Skull appears with other Kamen Riders and Monsters in Battle Spirits.

Other Media Appearances

The Q on the Radio/Targeted Princess

Kamen Rider Skull briefly makes an appearance in Kamen Rider W episode 13 "The Q on the Radio/Targeted Princess".

The S Terror/The Great Detective's Daughter

Sokichi Narumi makes an appearance in a flashback in episode 10 "The S Terror/The Great Detective's Daughter".

The B Carried on the Wind/The Beast Pursues

As well as in a flashback in episode 31 "The B Carried on the Wind/The Beast Pursues".

Big Sleep

During the encore at Koji Kikkawa's concert at the NHK Hall, Kikkawa appeared dressed up as Sokichi Narumi and performed the song "Big Sleep". At the same time, he was joined on stage by Kamen Rider Double.

Nobody's Perfect

Sokichi Narumi and Kamen Rider Skull are the main characters in the side-story presented in the "Nobody's Perfect" music video, a song credited to Narumi but sung by Koji Kikkawa. In the music video set during his life and prior to Philip's freeing, Narumi takes on a case of a kidnapping by the Museum of a young girl. He crosses paths with several Masquerade Dopants and the Terror Dopant, fighting and driving away the latter as Kamen Rider Skull.

Futo Detective (manga)

The Boss (Futo Detective)

Sokichi Narumi in an old photograph as seen in Futo Detective.

In the first chapter of the Futo Detective manga, Shotaro tries to take a "cool" picture of himself, which Akiko compares to a old picture of her late father and claims the latter is still more hardboiled than Shotaro is, much to his annoyance. In a later arc, Shotaro tells Tokime how he met Sokichi in 1999 and eventually mentored by him, letting Sokichi become a main focus of the story for this event.
The Boss in 2019
Koji Kikkawa did a photo shoot and interview in the July 2019 issue, complete with a photo showing what Sokichi would look like if he were alive in 2019.



A hard boiled person who helped the citizens of Futo as both a detective and as Skull, Sokichi lived and died while helping others. At a younger age, Sokichi was already a rather cheerful man with his partner Matsu while sometimes showing a comical and stubborn side. As well as helping Shroud through sheltering her, Sokichi still called Matsu his partner despite his betrayal and crimes later on. It seems the confrontation and death of Matsu combined with no longer being able to meet Akiko again has changed Sokichi though, as he seemingly became less cheerful and more cold.

Although he seemingly wasn't with Akiko much in her childhood, Sokichi clearly cared for her which was shown when he became motivated through talking with her on the phone. This fatherly side is also shown through his mentoring of Shotaro whom he acted both strictly and understandingly. He is quite forgiving towards others as he forgave not only Matsu, but Shotaro as well when he indirectly caused his own death. He was also the one who convinced Philip to make his own decisions right before his (Sokichi) death.

While mostly good, Sokichi was also somewhat the opposite of Shotaro as he mercilessly caused the Bat Dopant to die a painful death as well as allowed Bito to lie and turn himself to the police without a word. He also didn't say a word about Matsu's death but instead quietly walked away. Another difference was that Sokichi had a policy about using Gaia Memories which somewhat caused him to die whereas Shotaro uses them quite frequently as well as being proud to be Double and Joker. Although Sokichi died, his will continues to live on through Shotaro and the others as he seemingly continues to support them through spirit.

As the man who solved cases for Futo, Sokichi was both a good teacher and detective. He also fought against Museum as Skull. Even without transforming into Skull, Sokichi managed to hold his own against the Spider Dopant as well as defeating him and the Bat Dopant in Skull Crystal Form. He also managed to both lift part of a Shovel car that was crushing him as well as kicked it away when motivated. In his Default Skull Form, Sokichi fought evenly against the Taboo Dopant as well as seemingly overpowered the Terror Dopant himself. This is notable as Skull's stats are much lower than both Double and Accel's strengths showing how skilled he is. He later on appeared as a ghost to Shotaro where he showed him why Philip wasn't acting his usual self as well as giving his Lost Driver for Shotaro to use.


KR-Skull Crystal

Skull Crystal

"Skull! (Deep guitar riff to high guitar screech)"
―Transformation announcement[src]

Kamen Rider Skull Crystal (仮面ライダークリスタルスカル Kamen Raidā Sukaru Kurisutaru) is Skull's incomplete form. It differs from Kamen Rider Skull's standard form in that the helmet is iridescent and it lacks the S-shaped "crack". Skull Crystal is able to attack by releasing energy from his chest in the shape of a large purple skull that can bite opponents. This form is named after the crystal skulls.

This form is exclusive to Kamen Rider × Kamen Rider OOO & W featuring Skull: Movie War Core.


Kamen Rider Skull

KR-Skull Without Hat

Kamen Rider Skull (Without hat)

"Skull! (Deep guitar riff to high guitar screech)"
―Transformation announcement[src]

Rider Statistics

  • Rider Height: 205cm
  • Rider Weight: 110kg

Ability Perimeters:

  • Punching Power: 2 t.
  • Kicking Power: 6.5 t.
  • Maximum Jump Height: 45 m.
  • Maximum Running Speed: 100 m. per 6.3 sec.

Through the use of the Lost Driver and Skull Memory, Sokichi transforms into Kamen Rider Skull. Skull is unique in that besides wearing a white tethered scarf he also wears a white fedora. It is revealed that he was the original user of the quote "Now, count your crimes!" (さあ、お前の罪を数えろ! Sā, omae no tsumi o kazoero!), a quote now used by his successor. Skull's motif is that of a human skull and the letter S. Like Skull Rider, Skull appears to be a homeage to Skull Man, Shotaro Ishinomori's previous creation, who was adapted for the creation of Kamen Rider 1. Kamen Rider Skull's primary finisher is the long range shooting attack Skull Punisher (スカルパニッシャー Sukaru Panisshā), the Maximum Drive ability of his Skull Magnum. In Skull: Message to Double, Skull is shown to have a second Maximum Drive, known only as Finisher Kick (必殺キック Hissatsu Kikku), that involves releasing a giant energy skull from his chest, which stuns the opponent and knocks them back before rising into the air. Skull then puts the Skull Memory into the Maximum Drive Slot, jumps up, and does a roundhouse Rider Kick, which propels the energy skull toward the opponent, whom it bites down on. Kamen Rider Skull also appears as one of the Kamen Riders summoned by Kamen Rider Diend's Complete Form and his Gekijouban Card. In this appearance, his Maximum Drive attack is a generic Rider Kick, similar to Rider 1's famous somersault and kick attack, but with a purple swirling energy around Skull's right foot. In Ganbaride, the name of Skull's generic Rider Kick is Silhouette Kick (シルエットキック Shiruetto Kikku).

Appearances: Movie War 2010 (flashback), A to Z/The Gaia Memories of Fate, Movie War Core





Legend Rider Devices

Kamen Ride Skull

Kamen Ride: Skull

Skull Medal

Skull Medal

Skull Medal (スカルメダル Sukaru Medaru): Based on Kamen Rider Skull.

Clearer Skull Ring

Skull Ring

This Rider Ring which bears the likeness of Kamen Rider Skull is exclusive to Kamen Rider Wizard's Wizard Ring toyline. When used by a WizarDriver wearer, it would be able to summon Kamen Rider Skull.

Skull Lockseed (スカルロックシード Sukaru Rokkushīdo): Allows the user to transform into Skull Arms. The core image depicts the Lost Driver while the lid backside image depicts the Skull Memory. Gaim/Kurokage/Bujin Gaim/Kamuro-styled Lockseed.

  • Transformation: Skull Arms: Otoko-michi Hardboiled! (スカルアームズ・男道、ハードボイルド! Sukaru Āmuzu - Otoko Michi, Hādoboirudo!, lit. "A man's path, Hardboiled")
    • Squash: Skull Punisher (スカルパニッシャー Sukaru Panisshā)
    • Au Lait: Nobody's Perfect (ノーバディーズパーフェクト Nōbadizu Pāfekuto)
    • Sparking: Now, count up your sins (さあ、お前の罪を数えろ Sā, omae no tsumi o kazoero)

"(Digital beeping) Skull!"
―Activation announcement[src]

"To be announced"
―Secondary activation announcement[src]

"Rider Time! Skull! Skull!"
―Transformation announcement in the Ziku-Driver's right-hand slot[src]

"(Right-hand Ridewatch's announcement)! Armor Time! Skull! Skull!"
―Transformation announcement in the Ziku-Driver's left-hand slot[src]

"To be announced"
―Finisher announcement in left-hand slot[src]

Skull Ridewatch (スカルライドウォッチ Sukaru Raidowotchi): Based on Kamen Rider Skull, this Ridewatch provides access to the SkullArmor. It is dated 2009.

Behind the scenes


Sokichi Narumi is portrayed by singer-songwriter Koji Kikkawa (吉川 晃司 Kikkawa Kōji). Kikkawa also performs the song "Nobody's Perfect" under the name of his character. As Kamen Rider Skull, his suit actor was Eitoku (永徳).

In Skull's appearance in Episode Yellow: Treasure de End Pirates, his suit actor was Riichi Seike (清家 利一 Seike Riichi).



Kamen Rider Skull Concept Art


  • Kamen Rider Skull is the only Kamen Rider to have a major role in a Movie War film, but not be a Main Rider.
  • Until the reveal of the Neo Decadriver in Kamen Rider Zi-O, Kamen Rider Skull was the only post-Decade Rider to have an official Kamen Ride Card and one of two post-Decade Riders to have a Rider Card (Double had a Final Form Ride Card). As such, for 9 years, Kamen Ride: Skull was the only Kamen Ride Card which refered to the depicted Kamen Rider as Kamen Rider rather than Masked Rider, as the official romanization of the Kamen Rider Series was changed from Masked Rider to Kamen Rider starting with W. Likewise, Double's Final Form Ride Card refered to them as Kamen Rider W.
    • While sounds for post-Decade Riders were included with the Complete Selection Modification Decadriver, releaed in 2015, they were never officially announced or released.
  • As shown in Movie War 2010, Sokichi's death was around Christmas Day.
  • It was revealed in Movie War Core on a calender in his office that he became a Kamen Rider in November of 1999, which in real world time would be two months before Kamen Rider Kuuga debuted.
  • Sokichi is the only character with a hat to remain intact as Kamen Rider. This explanation can be clearly seen as Sokichi always remove his hat before transfomation, the only thing that has never be done by Shotaro and the other latter rider user with a hat, Sid.
    • On a funny note, if Shotaro or Sid would remove their hat and tried to put it back to their head, the hat is definitely not fit well (W's helmet antenna will rip Shotaro's hat, Sigurd's helmet won't be able to be stuck with Sid's hat).
  • Kamen Rider Skull's presence on Diend's Complete Form is an anomaly. Aside from being from the series after Decade, he is a heroic Rider while the other seven Riders on Diend Complete Form are villains, specifically the villains of their respective Summer Movies. Of course, a more appropriate choice would be Kamen Rider Eternal, the villain of Kamen Rider W Forever: A to Z/The Gaia Memories of Fate. However since the Cho Den-O Trilogy was released during the run of Kamen Rider W, with Episode Yellow premiering over a month before the W summer movie, Eternal appearing would be problematic.
    • It is possible that the Kamen Rider Skull summoned by Diend Complete Form is actually the imitation version.
  • It is possible that Sokichi's body is immune to some of the effects of Gaia Memories as he managed to seemingly overpower the Terror Dopant in the music video "Nobody's Perfect" without succumbing to his powers.
    • This may explain why Shroud gave him the Skull Memory and a Lost Driver.


See Also

Narumi Detective Agency
Shotaro Hidari - Philip - Akiko Narumi - Sokichi Narumi† - Tokime
Double Driver - Accel Driver - Lost Driver - Gaia Memories - Memory Gadgets - Fang Memory - Xtreme Memory - Trial Memory - Gaia Memory Enhancing Adapter - Metal Shaft - Trigger Magnum - Engine Blade - Skull Magnum - Prism Bicker - Eternal Edge - RevolGarry - HardBoilder - Gunner A - Shroud Magnum - SkullBoilder - SkullGarry
The Fuuto Irregulars
Santa-chan - Watcherman- Queen & Elizabeth - Isamu Bito
Futo Police Department
Ryu Terui - Mikio Jinno - Shun Makura
Museum and the Dopants
Foundation X
The Sonozaki Family: Terror - Claydoll - Taboo/R Nasca - Nasca - Smilodon - Masquerade Dopants
Dopants: Magma Dopant - T-Rex Dopant - Money Dopant - Anomalocaris Dopant - Cockroach Dopant - Sweets Dopant - Virus Dopant - Violence Dopant - Arms Dopant - Bird Dopant - Ice Age Dopant - Triceratops Dopant - Liar Dopant - Puppeteer Dopant - Invisible Dopant - Nightmare Dopant - Beast Dopant - Zone Dopant - Yesterday Dopant - Quetzalcoatlus Dopant - Gene Dopant - Jewel Dopant - Old Dopant - Utopia Dopant - Energy Dopant
Movie Exclusive Villains: Dummy Dopant - Heat Dopant - Trigger Dopant - Metal Dopant - Luna Dopant - Cyclone Dopant - Bat Dopant - Spider Dopant - Kamen Rider Eternal - Commander Dopant - Eyes Dopant
Manga Exclusive Villains (Futo Detective): Road Dopant - Aurora Dopant - Meganeura Dopant -Brachiosaurus Dopant - Scream Dopant - Alcohol Dopant - Puzzle Dopant - Reactor Dopant
Katsumi Daido - Maria S. Cranberry - Reika Hanehara - Kyosui Izumi - Gozo Domoto - Ken Ashihara
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