I read three novels of a chinese author in which all three of the protagonists of the respective novels seem to be sisters. But, in two of those, only hints were given that they were from Earth and last one stated that "Before her, her two sisters had also disappeared, but she had a hunch that her sisters were alive because the vitality in them was stronger than anyone else." All three protagonists have the same surname An being An Xiao, An Yi and An Bu respectively. I suspect them to be sisters because of the same surname, same origin planet, line stated in the last novel and that no other protagonists of the same author has the surname An. I want to know if these three novels would be considered to be in the same universe or not? Or if not, then what are they - spin-offs or something? How are these related?
Author: 雪原幽灵 (in NU) Book 1 (Protag: An Xiao): 成为“男”神的女人 / The Woman who Became the “Male” God Book 2 (Protag: An Yi): 雕骨师 / Bone Sculptor Book 3 (Protag: An Bu): 我的尸身放荡不羁 / My Corpse is Bohemian
I don’t know if they are sisters, but I they should be from the same family in the same universe. All three books are under the series in jjwxc with the title “An Family’s Three Stars.”