These are novel illustrations that were included in volume 6.
Front and Back Cover
Front Cover
Green Grandeur, Purple Thorn, Ivory Tower, Yellow Radio, Blue Knight and Scarlet Rain
Shinomiya Utai
Ardor Maiden
Kuroyukihime, Haruyuki, Fuuko, (Utai), Chiyuri and Takumu
Color Wheel
Page 009
Character Description
Page 023
Page 051
Page 081
Page 109
Page 157
Page 171
Page 205
Page 246
Page 269
Page 303