Namine (sorry it's so short but this was all I could think of!):
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“Okay, I don’t get it. If you were created from my Heart, why are you a boy?”
Namin blushed and let out a soft cough at the inquisitive look Kairi was giving him. “Well, you know your Heart spent some time in Sora’s body, right?” At Kairi’s nod, he continued, “Well, aside from allowing me to influence his memories, it… well, being in a boy’s body for a while influenced me when I was formed and made me a boy.”
The redhead’s mouth hung open in surprised understanding. “Oh.”