This article is about a/an rider in Kamen Rider Decade. |
- For the World of Negatives version, see Natsumi Hikari (A.R. World).
Natsumi Hikari (光 夏海 Hikari Natsumi) is a young woman who works at the Hikari Photo Studio under her grandfather, Eijiro Hikari while traveling through the A.R. Worlds with Tsukasa.
Eventually, she becomes Kamen Rider Kiva-la (仮面ライダーキバーラ Kamen Raidā Kibāra, Masked Rider Kiva-la), a Kamen Rider appearing in Kamen Rider Decade: The Last Story. Similar to other riders in the series, Kiva-la is an original Kamen Rider with origins coming from an A.R. World. Though unlike them, Natsumi does not come from an A.R. World and only used her powers twice.
Contents
Biography
Prior to the series, Natsumi was a member of the Taigaku Club (or TG Club for short) with a group of friends. The club was created for students who intended to drop out of high school to find their own answers in life. Eventually, they changed their minds and decided to finish high school, dissolving the TG Club and promising to meet each other again later on.
At the start of the series, Natsumi has nightmares about a mysterious Rider know as "Decade" and later discovers his belt and cards in the destruction of her world, giving them to Tsukasa. Knowing the dangers, Natsumi decides to accompany him on his journey anyway.
She occasionally uses the Hikari family's "secret technique", the Laughter Point (笑いのツボ Warai no tsubo), to keep Tsukasa and others in line by striking a pressure point on the target's neck that causes them to laugh uncontrollably. It's possible she has feelings for Tsukasa, and it is often hinted at during conversations with Yusuke.
Despite Narutaki's offer to save her, Natsumi chooses to stay with Tsukasa until the end of their journey, not believing him to be "the destroyer of worlds" that Narutaki makes him out to be. However, she starts to worry after hearing from Narutaki later on that Tsukasa's actions are actually destroying the worlds rather than saving them.
World of Shinkenger
In the World of Shinkenger, she assures Tsukasa that the Hikari Family Studio is as much Tsukasa's home as where he came from, as it is the place that he "always returns to". The Arrival of the Samurai Sentai Heretic Rider, Go Forth!
World of Black RX
In the World of RX she puts herself between Apollogeist and Tsukasa, deflecting Apollogeists's Perfecter, which was meant to drain the life energy from Tsukasa to prolong Apollogeist's life. Eventually she succumbs to the injury and dies in the hospital, as Daiki prevents Tsukasa from retrieving the Perfecter in time to save her life, but Tsukasa gives up part of his own life energy to revive her. In the World of Amazon she starts to truly wonder if there is a point in their journey, but continues in spite of that doubt. RX! Dai-Shocker Attack Black × Black RX
World of the Rider War
In the World of the Rider War, she is kidnapped by Apollogeist, who intends to make her his bride and feed off of her life force. She is saved by her comrades, but her nightmares become reality and the Rider War begins, despite their efforts to stop it.Rider War: Prologue Destroyer of Worlds
Movie War 2010

Natsumi's transformation into Kiva-la
In Decade: Final Chapter Natsumi and her grandfather live alone again, after Tsukasa becomes Violent Emotion, Decade begins systematically eliminating all Kamen Riders, Daiki Kaito disappears, and Yusuke Onodera chases after Decade. She tries to convince Decade to stop what he's doing, but fails to make him see things her way. Instead, she becomes Kamen Rider Kiva-la, and fulfills her role as Decade's destroyer, as he allows her to kill him. Before dying, Tsukasa hands her the Kamen Ride Cards that the other Kamen Riders turned into after their defeat and asks her to remember them. The other Kamen Riders are revived, and Decade disappears.
After being told of Tsukasa's true role, she seeks out a way to revive him and succeeds by developing a half-exposed photo negative from inside Tsukasa's camera. Because it is a photo Natsumi took herself, it isn't warped, and she and the other A.R. Kamen Riders are able to fill in the blank areas of the photograph with their memories. Reunited with the rest of the group at last, Natsumi becomes Kamen Rider Kiva-la again to stop Super Shocker with Tsukasa, Daiki, and Yusuke and saves her grandfather after he reverts from Super Doctor Death. She is last seen with her friends taking a picture after the conflict, after announcing their intent to continue traveling together.
Video Game Appearances
Kamen Rider Buttobasoul

Kamen Rider Kiva-la Medal
Kamen Rider Kiva-la is a playable character in Kamen Rider Buttobasoul.
Kamen Rider Battle: Ganbarizing
Other Game appearances
Masked Rider Expansion

Kamen Rider Kiva-La Masked Rider Expansion card
Kamen Rider Kiva-La appears as a playable character in this trading card game with other Heisei era and Showa era riders.
Forms

Kamen Rider Kiva-la
- "Henshin!"
- ―Transformation announcement via Kiva-la[src]
- Height: 175 cm
- Weight: 60 kg
- Punching power: 3 t
- Kicking power: 6 t
- Maximum jump height: 70 m
- Maximum running speed: 100 m per 7 seconds
Natsumi transforms into Kamen Rider Kiva-la (仮面ライダーキバーラ Kamen Raidā Kibāra) with the aid of Kiva-la. Kamen Rider Kiva-la is armed with the Kiva-la Saber, which she can use to perform her finishing attack, the Sonic Stab (ソニックスタッブ Sonikku Sutabbu): Kiva-la deploys wings of light from her back and flies toward the enemy at high speeds before slashing them.
This form is exclusive to W & Decade: Movie War 2010.

Rod Form
- "Rod Form!"
- ―Transformation announcement[src]
- Rider height: 187 cm[1]
- Rider weight: 102 kg[1]
- Punching power: 4.5 t[1]
- Kicking power: 9 t[1]
- Maximum jump height: 20 m[1]
- Maximum running speed: 100 m per 9 sec[1]
When possessing Natsumi (or anyone else) or by himself Urataros can assume Rod Form. The DenGasher forms into a rod-style weapon in this form. Rod Form gains the ability to fight underwater, extra protection, and increased kicking power, while losing speed and jump height. This is one of the more least seen forms as Urataros rarely fights but comes through when a fight is close to water or when the other Imagin are unable to fight. Rod Form is also one of the two base forms that have a Rider Kick, the second is Sword Form in the Cho Den-O Series. Urataros throws his rod like a harpoon then after a hexagonal symbol appears he attacks with a flying side kick. The Aura Armor and DenKamen mask resembles a Sea Turtle, the animal associated with the story of Urashima Taro.

Ax Form
- "Ax Form!"
- ―Transformation announcement[src]
- Height: 185 cm[2]
- Weight: 93 kg[2]
- Punching power: 8 t[2]
- Kicking power: 5 t[2]
- Maximum jump height: 30 m[2]
- Maximum running speed: 100 m per 7 sec[2]
When possessing Natsumi (or anyone else) or by himself Kintaros can assume Ax Form. In this form the DenGasher forms an ax for short ranged attacks. Ax form gains increased punching power and defense but loses speed and kicking power. This form is Den-O's physically strongest base form due to Kintaros' own brute strength. Kintaros tends to fight as Den-O whenever he senses crying or when hears anything similar to the Japanese word for cry (naku). The aura armor is golden yellow and the motif is of an axe, with a DenKamen Mask resembling the kanji for gold. All of which are elements to the story of Kintaro.

Gun Form
- "Gun Form!"
- ―Transformation announcement[src]
- Height: 197 cm[3]
- Weight: 98 kg[3]
- Punching power: 6 t[3]
- Kicking power: 10 t[3]
- Maximum jump height: 42 m[3]
- Maximum running speed: 100 m per 4 s[3]
When possessing Natsumi (or anyone else) or by himself, Ryutaros can assume Gun Form. The DenGasher forms a gun for short and long ranged attacks. Gun Form displays an increase in power, speed, and defense easily making it the most superior out of Den-O's four basic Imagin forms. Ryutaros tends to fight at his whim as he overpowers the other Taros and Ryotaro himself. However he tends to cause more collateral damage than the other forms due to his low precision and the high power of his ammunition. Ryutaros incorporates break dancing into his fighting style making his movement somewhat unpredictable. The Aura Armor and DenKamen resemble a dragon, the animal associated with Tatsu no ko Taro.

- "Soiya! Natsumikan Arms!"
- ―Transformation announcement[src]
- Height: 175 cm
- Weight: 60 kg
- Punching power: 6.7 t
- Kicking power: 10.2 t
- Maximum jump height: 28 m
- Maximum running speed: 100 m per 5.9 seconds
In a S.I.C. HERO SAGA story, Natsumi travels to the World of Gaim and gets a blank Sengoku Driver with a Natsumikan Lockseed. She later used them to transform into Kamen Rider Gaim Natsumikan Arms (仮面ライダー鎧武ナツミカンアームス Kamen Raidā Gaimu Natsumikan Amusu). This version of Gaim has a different helmet and crest from the original Gaim.
In this form, she is armed with the Musou Saber and Daidaimaru.
Equipment
Devices
- Den-O Belt - Transformation belt
- Rider Pass - Train pass used in transformation
- Kiva-la: Natsumi's Kivat partner
- Sengoku Driver - Transformation device
- Lockseeds - Gives access to Gaim's Arms changes, depending on which lock is used
Weapons
- DenGasher - a four-piece standard issue assemble side-arm that reconfigures to form various weapons.
- Kiva-la Saber: Personal weapon
- Musou Saber Holster - Carrier strap for Gaim's Musou Saber
Imagin Possessions
Behind the scenes
Portrayal
Natsumi Hikari was portrayed by Kanna Mori (森 カンナ Mori Kanna). As Kamen Rider Kiva-la, her suit actor was Yuuki Ono (小野 友紀 Ono Yuuki).
Meme
A recurring running gag in the series when Natsumi heard something is not really right or getting into some troublesome actions by someone else will cause Natsumi fustrated and performing the Laughter Point into the side of their necks with a thumb. This meme is also appeared in Kamen Rider Decade: Final Chapter, where she used the technique at the Shocker combatant.
Notes

An unused Kiva-la suit shows different details.
- Production photos reveal that Kamen Rider Kiva-la's suit originally featured a white belt, had a forehead crest painted solid purple rather than silver and gold, and lacked the black paint and yellow gem on her abdomen.
- Originally Kamen Rider Kiva-la was going to be the true form of Kiva-la, as shown in the original trailer for Kamen Rider × Kamen Rider W & Decade: Movie War 2010 attached to the finale.
- It is unknown how Natsumi can transform into Kamen Rider Kiva-la since she isn't a Fangire herself and it is fatal for humans to even transform into Kiva, dying from use afterward.
- However, since Kiva-la comes from an alternate world that has differences from the original series, she most likely doesn't have this restriction, meaning humans can transform with her.
- Her version of Kamen Rider Gaim as seen in the S.I.C. Hero Saga can be considered to be the A.R. World counterpart of the original Gaim.
- Her version of Gaim also takes inspiration from Kiva-la's design, with a bat-shaped crest along with armor pieces resembling those of Kiva-la's.
- Additionally, as a Natsumikan is a Hybrid fruit (between an Orange and Pomelo), it's appropriate that the form created by it is a Hybrid of Kiva-la and Gaim's Designs.
- Her version of Gaim also takes inspiration from Kiva-la's design, with a bat-shaped crest along with armor pieces resembling those of Kiva-la's.
Appearances
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 "TV Asahi's page for Den-O Rod Form". https://web.archive.org/web/20160307160342/http://www.tv-asahi.co.jp/den-o/rider/f/rodform.swf.
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 "TV Asahi's page for Den-O Ax Form". https://web.archive.org/web/20120825035109/http://www.tv-asahi.co.jp/den-o/rider/f/axeform.swf.
- ↑ 3.0 3.1 3.2 3.3 3.4 3.5 "TV Asahi's page for Den-O Gun Form". https://web.archive.org/web/20121017121335/http://www.tv-asahi.co.jp/den-o/rider/f/gunform.swf.