The Arpeggio is designed to resemble one large Nobody logo. The headstock of the sitar consists of three large, light blue spikes with blue bases. The neck of the sitar is blue with light blue, concave edges, and three yellow, pointed machine heads are visible on the left side of the weapon. Several yellow frets line the fretboard. The body of the Arpeggio is connected to the neck by a dull blue spike shaped like those on the Nobody logo, and the body itself is shaped like the lower half of the symbol. The shape of the symbol, particularly the circular indentations on the bottom of the sitar, is distinguished from the rest of the sitar by a light blue border. The sitar's saddle is yellow and its three strings are a very pale blue.
Musically, an arpeggio is the playing of notes from a single chord in rapid succession.
Arpeggio's ground combo starts with Demyx performing a 360° spinning diagonal slash with the tip of the sitar, followed by the same attack, but in the opposite direction. The next move of the combo involves Demyx swinging the sitar by the neck diagonally upward in a baseball bat-like fashion. The combo ends with another 360° spinning attack, after which, Demyx strums the sitar, emitting a yellow shockwave which damages any enemies around him.
The aerial combo consists of a downward diagonal slash with the tip of the sitar, followed by a thrust upward, and ends with four quick blasts of yellow shockwaves in an outward direction.