Demyx (デミックス, Demikkusu^?) was first introduced in Kingdom Hearts II. He is also referred to as the "Melodious Nocturne" (夜想のしらべ, Yasō no Shirabe^?). Demyx is voiced by Ryan O'Donohue in the English version of Kingdom Hearts II and Kenichi Suzumura in the Japanese version. Demyx first appeared in Kingdom Hearts II at Hollow Bastion with the other Organization XIII members. He later appeared in the Underworld,
the world in which he first removes his hood. He is confronted for
stealing the Olympus Stone, an object that protects the bearer from the
effects of the Underworld. He refers to Sora as Roxas, having been
given orders to "use aggression to liberate [Sora's] true disposition"
but nevertheless still proclaiming "they sent the wrong guy for this".
He fights Sora with the use of his water abilities and sitar^[4]
to create duplicates, giving the player a time limit to defeat them all
and leaving after losing. The two cross paths again at Hollow Bastion
during the Heartless attack, which involves Demyx's Dancer Nobodies.
Upon being reminded that he is a Nobody, and has no heart, Demyx
commands the "traitor" to be silent, and uses his duplicates and water
attacks;^[4] Demyx fades into darkness at the conclusion of the battle.