Eri Ikeda

Five descendants of the people showered with Bio Particles by Bio Robots five centuries in the past have become Biomen. They transform with the Bio Brace and fight using their Super Electronic Brains on their masks. Their Bioswords are equipped with sword and gun modes.

As a child, Ono Tsubasa saw a Shirato baseball game on TV and was amazed at the Trumpet player in the band playing. Now, in order to play the Trumpet, she enters Shirato High School. There, she meets Yamada Daisuke, a catcher for the baseball team. With each others support, they go towards their dream of playing at Koushien.