Kira's original Japanese voice is done by Hoshi Souichirou, a very well-known seiyuu. Some of his other roles include Goku from Saiyuki, Oujirou from Angelic Layer, Kain from Lost Universe, Gakuto from Prince of Tennis, and Kazuma from Scryed. Kira's English dub voice is done by Matt Hill. I've made clips of the same line in both Japanese and English for the sake of comparison:
» Hear a clip of Kira's Japanese voice
» Hear a clip of Kira's English voice
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