Vocal Album Vol. 9 for the game app World Dai Star: Yume no Stellarium. Focuses on songs performed by the unit "Sirius" from the in-game music. Includes familiar game tracks plus a duet version of "Worlds Dye Star" performed by Kokona Ohtori (CV: Manaka Iwami) and Shizuka (CV: Ikumi Hasegawa). Features newly drawn illustration jacket.