Koichi Hirose

Koichi Hirose *Profile:* - Nationality: Japanese - Age: 16-17 (during Part 4: Diamond is Unbreakable) - Personality: Kind, gentle, honest, determined - Background: High school student, lives with his mother Koichi becomes entangled in the world of Stands after encountering Jousuke Higashikata. Initially hesitant, he develops courage and loyalty, helping Jousuke in battles against Stand users. *Abilities:* - Stand: Echoes (, Ekō) - Acts as a series of evolving, incremental abilities (Echoes ACT 1-3) - Capabilities: 1. Sound-based attacks (ACT 1) 2. Enhanced strength and agility (ACT 2) 3. Reality distortion (ACT 3) *Relationships:* - Jousuke Higashikata: Mentor and friend - Yukako Yamagishi: Classmate, initially infatuated with him - Rohan Kishibe: Acquaintance and occasional ally