Nacht Faust, the Vice-Captain of Black Bulls and Morgen Faust, Nacht's younger brother twin, a member of Black Bulls.

Right now, they were fighting Lucius Zogratis, they were bleeding a lot and nearly had energy left.

Nacht and Morgen were losing consciousness as their vision started to blur, before they went fully consciousness. They heard a voice.

They can't see who it is but it sounds like you, their older sister?