Hikari no Sora no Qualia (光の空のクアリア, The Qualia of the Shining Sky), is a single by Cyua from BETTA FLASH. The song Hikari no Sora no Qualia was used as the opening theme for the third volume of the Nintendo DS adaptation of Higurashi no Naku Koro ni, entitled Higurashi no Naku Koro ni Kizuna: Rasen. It was released on June 10, 2009 by 5pb.. The second song on the single, Shikkoku no Saidan, was sung by Velforest.