Title Rondine di Pioggia ver. Vongola
Name Kojirou
Designer Unknown
Attribute Rain
Animal Swallow
Users Yamamoto
Abilities Concentrated Downpour
Cambio Forma Asari Ugetsu's Four Irregular Swords
Power C+
Intelligence B
Speed A+
Stamina A
Size 17cm
Personality Friendly
  • Charge
  • Rain Shield
  • Pecking
  • Waves
Manga Debut Chapter 240
Anime Debut Episode 75

Yamamoto's exclusive Box Weapon was created by remodeling a Rain-attribute Rain Swallow. It is imbued with Vongola's latest technology. Along with the Rain Dog, this is one of the two Box Animals that make up Yamamoto's Vongola Box. Yamamoto has named it "Kojirou".



Cambio Forma: Asari Ugetsu's Four Irregular Swords

Its basic performance is the same as the normal Rondine di Pioggia, but it can combine with Yamamoto's Shigure Kintoki through Cambio Forma to change its shape into the longsword-style weapon that was used by the First Rain Guardian. Also, as shown during the Choice Battle, it is capable of raining down Flames with the Tranquility effect over a large area.

  • Cambio Forma: Asari Ugetsu's Four Irregular Swords - Composed of the longsword created by the fusion between Kojirou and the Shigure Kintoki along with the three short-swords provided by Jirou. The longsword's hilt possesses wings-like decorations and a single jewel with the Roman Numeral "I" in the middle. During the rematch between Yamamoto and Genkishi, the Rain Flames released by it were able to slow down the enemy's own Flame-based attacks to the point they seemed to not be moving at all.


  • It takes its name from the sword-master famous for the "Tsubame Gaeshi" (lit. Swallow Reversal) sword technique.
    • On another note, the swordman Kojirou was also known for his skill with the nodachi Japanese longsword. His personal blade was called Monohoshizao (roughly Laundry-Drying Pole).
  • If you remove "Ko" from the name Kojirou, you get "Jirou," the name of the other half of the Rain Vongola Box.


Box Weapons
Sky Box Weapons: NatsuNatsu (Version X)Bester (Sky Lion Mode)Bester (Sky/Storm Liger Mode)Bester (Platinum Armor Sky/Storm Liger Mode)ScuderiaScuderia (Sky Pegasus Mode)White DragonBlack DragonsSky Turtle
Storm Box Weapons: UriUri (Leopard Mode)Uri (Version Vongola Box)Uri (Version X)MinkStorm Box of CarnageStorm ScorpionsStorm MoleStorm SerpentStorm Stag BeetleStorm BatsStorm HyenaSistema C.A.I.Flame ArrowDark ScytheSpikesDark SlicerFlying CarpetThrone
Rain Box Weapons: JirouKojirouKojirou (Version Vongola Box)Jirou (Version X)Kojirou (Version X)AloAlfinRain Box of CarnageRain OwlRain Giant SquidRain PelicanHeavy Rain ElephantVampire BatRiding CropWater
Sun Box Weapons: KangaryuuKangaryuu (Version Vongola Box)Kangaryuu (Version X)Sun RhinoSun Box of CarnageKuuSun SpidersSereno GlovesSun TrowelMelone Base‎‎RopeOctopus Head
Lightning Box Weapons: GyuudonGyuudon (Version X)Colulu & WidgetColulu & Widget (Black Foxes Form)LivyaElectric Wild BoarElectric HornetElectric FireflyElectro MantisLightning BirdElettro BilliardTurbine Shoulder ArmorElectro LanceLightning SquidLightning Starfish
Mist Box Weapons: Mukuro (Mist Owl)Mukuro (Vongola Mist Owl)Mukuro (Version X)Spectral Sea SlugsFlan's Box WeaponMist Box of CarnageMist Sea SnakesMist StarfishNuvola GauntletIllusion SwordSuit of ArmorParachute & Balloon
Cloud Box Weapons: RollRoll (Version Vongola Box)Roll (Version X)ZamzaCloud Box of CarnageNuvola VelociraptorDemon BearCloud MothBellflowersCloud TonfaCloud WhipViolet Tornado

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.