Shoose (left) and aisu (right) as seen in their article in Utattemita no Hon July. Illust. by ave (あヴぇ)
Shooaisu (しゅーあいす) is the duet unit betweet Shoose and aisu. They share a particularly close relationship with each other, the two are occasionally referred to as "twins" (双子, futago) due to their mutual chemistry and the complimentary nature of their voices. Their collaboration unit "Shooaisu" (both a portmanteau of their names and a pun on the Japanese term for ice cream puffs, as a homage to their shared love of sweets) have since released an album: Kuusou Capsule.