Seira Otoshiro
Screen Shot 2014-02-20 at 8.32.55 PM
Kamen Rider Jam
Kamen Rider Den-O Sword Form
Gender: Female
Series: Aikatsu!
Motif: Apple
Homeworld: Earth
First Appearance: Kamen Rider x Super Sentai x Metal Hero x Tomica Hero x Pretty Cure x Aikatsu!: Super Hero Taisen W
Number of Episode
3 (movies)
Full list of appearances
Actor: Kaori Ishihara


Kamen Rider Jam

Den-O (Let&#039;s Go Kamen Riders)</div>

Kamen Rider Den-O Sword Form

"If you're 'do' then I'm 're'. If you're 're' then I'm 'mi'. I'll always be a step ahead of you!"
―Seira's main catchphrase.

Seira Otoshiro (音城セイラ Otoshiro Seira?) is one of the new main characters from the Data Carddass Aikatsu! 2014 Series and the related anime adaption for it (season 2). She is a rock-genre character and a cool-typed Aikatsu idol. Her favorite brand is Swing Rock. She appeared in Super Sentai x Kamen Rider x Metal Heroes All Stars Featuring Aikatsu!.

Seira is introduced as being one of the main students representing Dream Academy. She is announced as the Ranger of the Cool Angels in episode 70.



Seira has pink hair, which is as long as Ichigo's, tied up into a ponytail and has orange eyes. She sports a purple, poofy ribbon on her ponytail. When she revealed herself to Aoi and friends, her hair wasn't tied.


She is a leader type and loves rock songs. She used to play classical music instrument and devoted herself to rock after playing guitar. She also seems to toy with juices.


Otoshiro (音城?): Oto (?) means Sound. Shiro (?) means Castle. This could be a reference to her being talented in rock music and having a perfect pitch.

Seira (セイラ?) means Holy and Good.


Rider Powers

Like with the other Armored Riders, Kamen Rider Jam's forms are called Arms (アームズ Āmuzu?). Only in movie of Super Hero Taisen X, she briefly transformed into Kamen Rider Den-O Sword Form after possessed by Momotaros.

Jam Pre Arms

Ride Wear

The Ride Wear (ライドウェア Raido Uēa?) is Jam's default form undersuit, which is briefly seen during Jam's transformation sequence before the Armor Part attaches or when she changes Arms. However, this form is completely vulnerable to any incoming attacks when shot at directly in the suit rather than at the Arms that is descending down on the Rider.

Jam is one of only a few Armored Riders who are defaultly equipped with a Musou Saber side weapon. However, unlike the others, his Sengoku Driver does not come with a holster, while the Musou Saber itself was not even visible until it appeared without notice in the middle of battle.

The Ride Wear that Jam's Sengoku Driver has is easily identifiable through its Rider Indicator (ライダーインジケーター Raidā Injikētā?) faceplate. The Rider Indicator only identifies what Ride Wear a Sengoku Driver contains for simplicity and can be replaced with extensions such as the Genesis Core or Senyo Joint.

Darkness Arms

Darkness Arms

"Darkness Arms: Ōgon no Kajitsu! (Sinister choir with harp music)"
―Transformation announcement[src]
  • Height: 209 cm.
  • Weight: 117 kg.

Ability Perimeters:

  • Punching power: 18.5 t.
  • Kicking power: 19.6 t.
  • Maximum jump height: 22 m.
  • Maximum running speed: 100 m. per 6.2 sec.

Darkness Arms (ダークネスアームズ Dākunesu Āmuzu?) is Jam's default apple-based Japanese Samurai form. Accessed through the Black Ringo Lockseed, this form's Arms Weapon is the Dark Daidaimaru, while the helmet Jam wears is the Black Mask (ブラックマスク Burakku Masuku?) with the Steering Eye (ステアリングアイ Sutearingu Ai?) visor. This form debuts in episode 47.

This form is substantially weaker than Mars due to the fact that the Golden Ringo Lockseed was depleted of all its energy, turning it into the Black Ringo Lockseed. Kougane has stated that he has only been able to regain very little of its power back. Despite that, by pure numbers, he does have the strongest punch out of all the Armored Riders, beyond even Gaim, is second to only Kachidoki Arms for kicks and barely is stronger than Duke, can jump as high as Gaim and Baron in Pine Arms and Mango Arms, and barely outpaced by Baron and both Zangetsu and Zangetsu-Shin. In fact it possesses the same punching and kicking power as the Golden Arms, but is faster and can jump higher. Despite this fact, Jam appears to have very low defensive capabilities to the point where even Ryugen was able to injure him alone whereas Mars was able to fight against the surviving Riders in the Soccer World.

This Arms' Rider Shooting-based finishing attack has two variations depending on which function Jam activates from his Sengoku Driver.

  • Squash: Jam summons up to 15 energy apples, then slashes an energized Dark Daidaimaru to send them flying so as to bombard the enemy.
  • Au Lait: Jam summons a bigger energy apple, then jabs the Dark Daidaimaru into it, sending it flying at the enemy.

Appearances: Episode 47

Sword Form

Kamen Rider Den-O

"Sword Form!"
―Transformation announcement[src]
  • Height: 190cm
  • Weight: 87kg
  • Punching power: 5t
  • Kicking power: 7t
  • Maximum jump height: 35m
  • Maximum running speed: 100m/5.2s

Seira was also once possessed by Momotaros, who then used the Den-O belt to transform into Sword Form

Appearances: Super Hero Taisen X


In the past, she plays classical instruments but moved on to rock when she first played the guitar. Like Ichigo, her family owns a restaurant.


"La la la!"
―Seira's happy phrase
"An uncountable number of dreams awaits just around the corner!"
―From episode 100


  • Her zodiac sign is Scorpio.
  • Seira is the second character, after Kaede, to use Premium Rare Cards for her debut.
  • Her aura contains notes, lightning and a chain-looking chandelier with crystals.
  • She has a little sister.
  • She shares her singing voice with Aoi Kiriya.


Discussions about Seira Otoshiro

You can find discussions about everything related to this wiki on Aikatsu Wiki Forum!

Ad blocker interference detected!

Wikia is a free-to-use site that makes money from advertising. We have a modified experience for viewers using ad blockers

Wikia is not accessible if you’ve made further modifications. Remove the custom ad blocker rule(s) and the page will load as expected.