Ren Aoi is a mysterious man, who transforms into Kamen Rider Fifteen, created by the Badan Empire in order to defeat the Kamen Riders. He is the father of Shu Aoi and husband of Saki Aoi.

Character History


Ren Aoi was once a family man when his wife was alive. After his son died in an accident, Ren falls into despair for losing him. In order to see her again, Ren joins the Underground Empire Badan, becoming their Armored Rider, in order to resurrect his son by using him to power Badan's mega-reversal machine. However, his son ran away from him, due to his father joining Badan. Once he discovered his son's whereabouts, he and the Empire go to Zawame City, the place that is also the source where the current Heisei Riders/Neo-Heisei Riders called Armored Riders created by Yggdrasill, and an alternate dimension Helheim where the Lockseeds and the Inves came from, which Badan may somehow take every one of Yggdrasill's data. Before hunting his son, he defeated and brainwashed most of the Showa Riders into believing that the Heisei Riders are nothing but nuisances and not actual heroes, as part of the plan of setting Zawame City up as a battlefield for all Riders from each era's side, with the losers being transformed into Lockseeds, then finally using his son once the Empire caught him.

ToQger vs. Gaim

Kamen Rider Fifteen first appears to fight the ToQgers, but is interfered by Showa Riders #1, #2, and V3. The three riders manage to drive off Fifteen, as he enters through a darker version of a Helheim Crack. During the post-credit scene, he foreshadows the events of Heisei Rider vs. Showa Rider: Kamen Rider Taisen feat. Super Sentai.

Heisei Riders vs. Showa Riders


Like his fellow Armored Riders, Kamen Rider Fifteen's forms are called Arms. But instead of normal fruit or nut Lockseeds, he uses the Heisei Rider Lockseed to channel the Legend Rider Lockseeds, allowing him to use the powers of the 15 Heisei Riders.

(guitar riff to ominous choir)
~ Transformation "announcement"
HD KR Fifteen 2

Fifteen Arms

Fifteen Arms is Fifteen's default skeleton-based form. Accessed through the Fifteen Lockseed, this form's Arms Weapon is the Bone Sword.

Similar to how Legend Rider Arms appear as the head of the represented Rider before transformation, the Fifteen Arms initally appears as a skull not unlike the original appearance of The Generalissimo of Badan.

Unlike other standard Lockseeds, there is no accompanying phrase, similar to most of the Energy Lockseeds.

(guitar riff) Decade Arms! Hakaisha on the Road!
~ Transformation announcement
15 10years Arms

Decade Arms

Decade Arms is a special form, based on Kamen Rider Decade's default form. Accessed through the Heisei Rider Lockseed channeling the Decade Lockseed, this form's Arms Weapon is the Ride Booker.

(guitar riff) Fourze Arms! Seishun Switch On!
~ Transformation announcement
1540 Arms with Barizun Sword

Fourze Arms

Fourze Arms is a special form, based on Kamen Rider Fourze's Base States. Accessed through the Heisei Rider Lockseed channeling the Fourze Lockseed, this form's Arms Weapon is the Cosmic Module Barizun Sword instead of the Rocket Module, which was used by Kamen Rider Zangetsu in the Kamen Rider × Kamen Rider Gaim & Wizard: The Fateful Sengoku Movie Battle.

(guitar riff) Wizard Arms! Shabadoobie Showtime!
~ Transformation announcement
15 Wizard Arms

Wizard Arms

Wizard Arms is a special form, based on Kamen Rider Wizard's Flame Style. Accessed through the Heisei Rider Lockseed channeling the Wizard Lockseed, this form's Arms Weapon is the WizarSwordGun.

(guitar riff) Gaim Arms! Fruits Yoroi Musha on Parade!
~ Transformation announcement
15 GAIM Arms

Gaim Arms

Gaim Arms is a special form, based on Kamen Rider Gaim's Orange Arms. Accessed through the Heisei Rider Lockseed channeling the Gaim Lockseed, this form's Arms Weapon is the Daidaimaru with the Musou Saber as a side weapon.



  • Sengoku Driver - Transformation device
  • Side weapons:
    • Bone Sword - Personal weapon both untransformed and in Fifteen Arms
    • Musou Saber - Secondary side weapon in Gaim Arms
  • Arms Weapons:
    • Ride Booker - Fifteen Decade Arms' personal weapon
    • Cosmic Module Barizun Sword]- Fifteen Fourze Arms' personal weapon
    • WizarSwordGun - Fifteen Wizard Arms' personal weapon
    • Daidaimaru - Fifteen Gaim Arms' personal weapon
  • Lockseeds - Gives access to Fifteen's form changes, depending on which arm the lock is.


  • The golden symbols on his head are actually the kanji characters Fifteen, the '15' motif being a reference to the showdown between the 15 main Heisei Riders and 15 Showa Riders.
  • Fifteen's design is reminiscent of several designs seen within the franchise:
    • His skeleton motif and black/silver color scheme is reminiscent of Kamen Rider Skull.
    • Fifteen also resembles the Oni Riders from Kamen Rider Hibiki.
    • Fifteen's primary color and ribcage on the chest mirrors the iconic Shocker Combatmen design.
    • The white mane and crown on his helmet is similar to that sported by Oni Brother Mimihiko.
  • Fifteen is similar to Sou Fueki (Kamen Rider Wiseman) in that they both became evil Kamen Riders to bring a loved one back to life.
  • The casting of Itsuji Itao as Ren Aoi is coincidental considering his aforementioned role in Kamen Rider The First as a reboot version of Spider Man, the first kaijin fought in Kamen Rider. Amadum, the villain of the two-part Kamen Rider Wizard epilogue which introduced Gaim and united the 15 Heisei Riders, was portrayed by Tomorowo Taguchi who previously played a reboot version of the first kaijin fought in Kamen Rider V3, Scissors Jaguar, in Kamen Rider The Next.
  • Fifteen is the first Evil/Movie Rider to alternate between different forms, just like main Riders have done in the Heisei era.
  • In an interesting coincidence, all of the Legend Rider Arms Fifteen uses have Gaim/Kurokage-styled transformation phrases.