The Body, along with the Heart and Soul, is a part vital to the complete existence of any living thing. The body gives the heart and soul a vessel, granting a person a physical appearance and a form. The body is a medium for a person's heart and feelings to be expressed in the physical world.
The Heart controls the body, much like the brain in the real world, so when someone becomes a Heartless, and their heart is released, they leave behind their body and soul, which is an empty shell and usually withers away. However, if that person's heart was strong enough, the soul will take control of the body and the shell will start to act on its own. A body being controlled by a soul with no heart is a being called a Nobody.
While the Heart is the deciding factor as to if a person can wield the Keyblade, the body can be used in a loophole for acquiring the Keyblade, as seen with Ansem, Seeker of Darkness and Riku in Kingdom Hearts. Xehanort's Heartless possessed Riku's body, therefore by controlling the heart and giving Xehanort's Heartless access to Riku's Keyblade-wielding powers.
According to the Secret Ansem Report 5, Ansem, Seeker of Darkness gave up his body and soul, but even then, he was able to control the other Heartless instincts. This could mean that Xehanort had so strong a heart, that, when he turned into a Heartless, he was able to control his own instincts as well as of the other Heartless'. Also, Xemnas, his counterpart, had his Soul so powerful, that was able to control all the lesser Nobodies, the same way as Ansem did.
According to the Secret Ansem Report 10, Naminé was born as a special type of Nobody when Sora attacked himself with the Keyblade, causing his and Kairi's hearts to leave their bodies simultaneously. Given that, Naminé is a special type of Nobody, made from Sora's Body and Soul, but at the same time with Kairi's essence.
|Kingdom Hearts • Chain of Memories • Kingdom Hearts II • coded • 358/2 Days • Birth by Sleep • 3D: Dream Drop Distance • χ [chi] • Back Cover • 0.2 Birth by Sleep • Kingdom Hearts III|
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|Re:Chain of Memories • Re:coded • Unchained χ • HD 1.5 ReMix • HD 2.5 ReMix • HD 2.8 Final Chapter Prologue|
|Kingdom Hearts Final Mix • Kingdom Hearts II Final Mix • Kingdom Hearts Birth by Sleep Final Mix|
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