She only appears briefly in Chapter II, greeting Marius when he returns home to their villa and comments that he looks handsome in his armor. She then says that his sister will want to see him, but Leontius instead steals him away first for a training session. After Marius and Leontius finishes sparring, Septima is heard screaming as she runs through the halls of the villa pursued by barbarians, and Leontius calls out to her before taking up arms to fight the assailants.
Marius and Leontius find Septima and Honorata lying dead in the reflecting pool of their villa's courtyard, moments after being slain. Upon seeing their corpses, Leontius angrily declares that he will kill every last one of the barbarians, and furiously rushes forward and kills the next one he sees.
When returning home to the villa in Chapter VII, Marius remembers finding her body and relives the moment in an out-of-body experience. Summer then appears and reveals to Marius that she was murdered under Emperor Nero's orders, who sought to kill Leontius and his entire family for inciting the public against him.