Masayasu Miyoshi is a member of the Miyoshi Trio, or Sanninshu. He, alongside Nagayasu Miyoshi and Tomomichi Iwanari led the Miyoshi clan after Nagayoshi Miyoshi’s death. The three acted as protectors for Yoshitsugu, Nagayoshi’s still adolescent heir. He is believed to be the historical inspiration for one of the Sanada Ten Braves.