Vivy was wary of her at first, as their mission is to stop her from colliding the Sunrise Hotel to the earth surface.
As the mission went on, Vivy knows her kindness and hospitality, treats her guests and hotel staff as a family, and teaching Vivy to smile, making her doubt that she was the culprit as Matsumoto suspects. She was also hesitant to leave Estella herself to control the hotel's collision course, as doing it will destroy herself too in the process.
In the end, as both twin sisters sacrificed themselves, Vivy resolves that their destruction will not be in vain, and will remember them with a smile.
Leclerc was Estella's co-worker and one of the first AI staff of the Sunrise Hotel.
She was very hospitable towards guests and other AIs and Estella thinks highly of her as treats her as a family member. She doesn't know that Leclerc collaborates with Toak to sabotage the sunrise hotel to destroy Estella, as she blames her for the former manager's death (even though Estella knows it was an accident).
Estella didn't know that Leclerc was destroyed by Elizabeth in the end.
Elizabeth was Estella's Twin AI Sister, whom she cherishes the most prior to becoming the manager of Sunrise Hotel.
She was the one who woke up 6 months before Elizabeth as a part of an experiment of shared consciousness and if Elizabeth can copy Estella's abilities. She and Elizabeth talked to each other through the wall, and shared their curiosity about life and if an AI can feel emotion like humans. In the end, the experiment ended up in failure and they didn't met in the end, as she was given a new mission as a caretaker AI of the Sunrise Hotel, while Elizabeth was discarded, which made her very sad.
Years later, they met each other at last, though it was a very short moment, as her and Elizabeth helped each other to avert the collision of the sunrise hotel to the earth surface.
In the Future, Elizabeth still ponders about her last moments, as she was perished while Elizabeth was still alive due to Toak archiving her data memories before the incident.