Rantaro Kiyama (黄山 乱太郎, Kiyama Rantaro), also known as The Boss (クミチョー, Kumicho) in the Japanese version and The Head Honcho or Honcho for short in the English version, is a character featured in the anime and manga series, Beyblade Burst. He is a member of the Beigoma Academy BeyClub as well as a member of the Spanish team: BC Sol. He currently battles with his Beyblade, Roktavor R3 4Cross Flugel. He is also the older brother of Ranjiro Kiyama.
(Source: https://beyblade.fandom.com/wiki/Rantaro_Kiyama)
