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...
Wouldn't have expected you to stay 
behind so your comrades could escape.
لم أتوقّع منك أن تظلّ في الخلف 
.ليتمكّن رفاقك من الهرب
No esperaba que hicieras de escudo
para dejar huir a tus amigos.
Não esperava que você ficasse para 
trás para proteger seus companheiros.