Rahna is an unseen character to whom Kaidan Alenko refers throughout his discussions with Commander Shepard. Born to a wealthy Turkish family, Rahna was one of the biotic potentials sent to BAaT when the Alliance and Conatix Industries first organized the training program. On Jump Zero, she had a close circle of friends, including Kaidan, who describes her as smart, charming and gentle: everybody loved her and protected her.
Rahna was terrified of her instructor, Commander Vyrnnus, and with good reason. When Rahna became exhausted under his brutal regime and tried to pick up a glass of water with her hand rather than use her biotics, Vyrnnus punished her by breaking her arm. Kaidan retaliated, lost control, and accidentally killed Vyrnnus with a "full on biotic kick". Though Rahna had been scared of Vyrnnus, now Kaidan scared her even more and things never worked out between them afterwards. It is unknown what happened to Rahna after BAaT was shut down.