At his core, Kira was a kind, compassionate, and selfless person who was willing to put his own life at risk to protect others without hesitation, especially his friends and loved ones. A strong believer in individualism, Kira firmly believed in the freedom of choice for all people and had a profound respect for life. Kira was an introvert by nature and spent long periods alone contemplating his thoughts and emotions but also enjoyed being with and talking to others. Despite being very intelligent, Kira could be stubborn and had the habit of entering into dangerous situations without thinking them through. However, this tendency, combined with his kindness towards others earned him the friendship, trust, and loyalty of many people.

Initially a pacifist, Kira disliked conflict and wanted nothing to do with war. However, he was forced to compromise his morals to defend his friends, leading him to fight against his fellow Coordinators.[6] Because of his highly sensitive and empathic nature, Kira became traumatized throughout his continuous exposure to war by the deaths he committed and the lives he failed to save.