"Ryuu no Tani to Taiyou no Toride" is an original song by Ishifuro featuring Fukase's Normal voicebank that was used as an official demonstration song. It is a rock ballad that tells a story about a boy who was raised by a dragon. Eventually he wants to see the human world and forgets about the valley where he grew up. The dragon is saddened but she accepts that the boy will be fine on his own and that she won't be anything more than a hindrance to him. This song is featured in the Fukase compilation album, VOCALOID Fukase ~THE GREATEST HITS~.