Cassandra Delos

Cassandra Delos is the youngest child of Castor and Noel Delos and Lucas Delos's baby sister. She is the reincarnation of her namesake Cassandra of Troy, the Trojan priestess and a daughter of King Priam. Similarly to her namesake, she is also the chosen oracle of her generation.

In the trilogy
Cassandra "Cassie" Delos' first appears in the first novel together with her cousins and sibling on the first day of school. She is introduced as Lucas's little sister and incredibly bright for her age. In the first novel she is only a freshman in high school, but is described as wise beyond her years. This is due to her superior knowledge of the past and future as the oracle and also due to her scion upbringing and education. As the oracle she is expected to pull away from her family, and humanity all together at a certain point. For this reason, her family cherishes every moment of happiness that can with her while she is still with them. There is also the very real and distinct possibility that she could lose her mind like many of the oracles before her, unable to bare the psychological and emotional trauma involved with being an instrument of The Fates. Over the course of the series Cassandra grows physically weaker under the strain of delivering prophecies, even once having been described as being more physically delicate than a mortal child. She is also shown to slowly start losing touch with the girl she once was, showing little sympathy and empathy to those around her as more time goes on. It is not until she meets Orion Evander that she begins to regain her sense of self and start expressing more genuine emotion.

Relationships
Orian Evander 

Cassandra and Orion first meet in the third novel, Goddess. Due to the events of the last book, Orion, Helen, and Lucas are brought back to the Delos compound at the start of the novel to heal from their respective injuries. Helen is awoken along with the rest of the house one night after hearing Orion screaming. They come to find out that this is because Cassandra had snuck into his room in the middle of the night and, not realizing she was asleep on the floor near the foot of his bed, accidentally stepped on her, causing her to bite him. From that moment on, Helen frequently observes Cassandra's seemingly inexplicable need to be near Orion. Cassandra is shown in multiple scenes to express anxiety and or fear whenever Orion is away, asking when he will be back and how long he will be gone. It is not revealed until later in the novel that the reason for this is because The Fates cannot control Cassandra as long as she is near Orion, but ultimately the reason for her attachment to him stems from the fact that she has fallen in love with him. While this should have seemed obvious, no one expected Cassandra to fall in love with Orion or anyone due to her status as the Oracle and The Fates unwillingness to share their vessel. However due to Orion's nature as 'The Shield', he possesses the unique ability to be able to block the fates from seizing control off Cassandra or intervening in her life as long as he is around, enabling her to fall in love with him. However, again due to being the oracle, Casandra's feelings are entirely dismissed by Orion in the beginning. It is not until the final battle that Orion realizes the true extent of Cassandra's feelings for him and that he reciprocates them as well.