Roka  

, ロカ

Yamato's best friend is Roka, who often serves as his second conscience due to his tendency towards danger or morally questionable actions. Roka was always afraid of the things that Yamato would do because he knew they could be dangerous or conflict with their moral code. Despite this fear, Roka followed Yamato on their journey and learned to become a stronger person through their adventures together. By the time they returned home, Roka had become wiser and braver than before. In After War, he returns as a scholar and wears glasses.