Kotarou's nickname is "Kotarou the Runner".  He's a master of defensive battles, and minimizing losses when things turn bad.  His quiet, unassuming nature and the way he fights make him less likely to stand out than his other friends.  However, if he was put up against a real foe, someone who he couldn't beat unless he gave up on running, you might just learn his true name...
Did he figure he'd rather be a 
Gundam than get called Zaku?!
هل فكّر في أنّه يفضّل أن يكون 
!غاندام مِن أن يُنادى بزاكو؟
Será que prefere ser um Gundam
 do que ser chamado de Zaku?!