Kako was a spoiled and self-centered coward with a severe inferiority complex. He acted as an errand boy for a group of bullies to avoid being the subject of their abuse, and his parents would let him get away with just about anything, much to his older sister's chagrin. Kako’s only "friend" was Kirie who also went to his school. Kako would constantly boss Kirie around since it made him feel less like a loser especially since Kirie would take this abuse without complaint. Kako in fact made Kirie accompany him to the nature school for this very reason. It was here that Kako developed a strong crush on Chizu. When he first entered the game Kako was excited, hoping that his piloting Zearth would make him famous, but upon learning the price of piloting, he suffered a mental breakdown and hid in his room.

(Source: Wikipedia)