Sirin is the Herrscher of the Void, this is an alternate timeline of Honkai Impact 3rd where she was adopted by Siegfried and Cecilia instead of dying in Siberia. 4 years have passed since the 2nd Eruption and she now lives peacefully with her family.
An AU where Kiana is living peacefully with her sister, Sirin in the dorm of St. Freya.
Raiden Mei is a protagonist of Honkai Impact 3rd along with Kiana Kaslana and Bronya Zaychik. She is the natural 3rd Herrscher of the Current Era and a member of the St. Freya team.
Kiana Kaslana is one of the main protagonists of Honkai Impact 3rd along with Raiden Mei and Bronya Zaychik. She is the adoptive daughter of Siegfried Kaslana, alongside being a vessel for the 2nd Herrscher — Herrscher of the Void. After the events of Chapter 25, she awakens as the Herrscher of Flamescion. Ultimately after the events of Chapter 35, her will was approved by the Cocoon of Finality, granting her its power and allowing her to awaken as the one and only true Herrscher of the End.