In SAI's Terminal Service, workers (humans) are always partnered with a giftia. There are four giftia's in Terminal Service 1. Those four giftias are: Isla, Constance, Zack, and Sherri/Sherry. Isla and Tsukasa are partners. (Isla's former partner was Kazuki.) Constance and Kazuki are partners. Zack and Michiru are partners. Sherri/Sherry and Yasutaka are partners, though Yasutaka tends to slack off or sneak off to his "lady friends".