Aiming to be a samurai, Yaiba and his father went to the jungle to train, but due to various circumstances they end up back in Japan and moving in with the Mine family. Yaiba only really cares about becoming a legendary samurai and loves to challenge strong opponents. He has taken up the legendary Raijin-ken and gone on numerous adventures to accomplish this. Despite this great dream, he is also bratty, frivolous, perverted, and gluttonous. He is the same age as Sayaka, although he is much shorter. Though usually not very bright, Yaiba is pretty clever when it comes to the sword and has thought up many special attacks on the spot. He is descended from the thunder god Susano'o and the heir to very wealthy Kurogane Group, although he is unaware of this until the final story arc.
In the three-way cross-over OVA, Yaiba battles Kaitou Kid, whom he mistakenly refers to as "Kancho Kid" (kancho is a popular prank amongst Japanese children where you put your index fingers together and poke someone in the butt), in order to prevent him from stealing the Mine family's treasured sword. Yaiba tries to protect the sword by tying it to his headband and belt, but Kid easily tricks him into looking away so he can undo the headband. After a brief swordfight Kid uses his hang glider to escape, but Musashi has Yaiba use a kite (transported by Kagetora in the original Magic Kaito chapter) to fight him in the air until Onimaru suddenly appears shoots them down with a cannon, causing Kid to finally give up and go home. The Magic Kaito chapter ends with both Yaiba and Kid saying to themselves that they don't want to sword fight ever again.
The OVA version portrayed Yaiba as being much younger, around the same age as the Detective Boys, rather than 14. When he introduces himself to the Detective Conan characters, the Detective Boys think he is trying to be Kamen Yaiba but dressed incorrectly. Yaiba misunderstands and thinks they misheard his name and then asks what a Kamen Yaiba is.
Swords and techniques
- Raijin-ken (雷神剣 Lightning God Sword)
- Ryuujin-ken (龍神剣 Dragon God Sword)
- Haou-ken (覇王剣 Ruler Sword)
- Kusanagi (クサナギ )
- Yaiba is unfamiliar with English accent.