Cassandra had always led a hard life, which resulted in her harsh demeanour. She was born to Alexandria Reynolds and Aeolus. Alexandria worked as a bartender at a local bar in New York City. The two met one night as the bar was beginning to close. She noticed a tall man with tan complexion, swept back jet black hair and sky blue eyes. Initially, she was annoyed by him but as the two exchanged flirtatious banter, both consuming a substantial amount of alcohol. They quickly headed to her apartment to consummate their hasty bond. A few months later, they both discovered that Alexandria was pregnant. Despite her affection and love for Aeolus, she became embittered at Aeolus, telling him to leave. When he did not comply, she threatened him with the life of the child. Relucrantly, he complied, but not before writing a letter for his unborn child detailing power, and a map showing Camp Half Blood. He also gave her an amulet which would part to form dual kusarigama.
As she grew up, she was verbally and physically abused by a mother who had never truly wanted her. Alexandria had grown bitter towards Aeolus and had refused her her inheritance. Alexandria also turned into an alcoholic, often beating her daughter in drunken fit of rage. She was quite terrified of her mother when she (her mother) was in one of her drunken rages and would often hide in her bedroom closet to escape reality. Cassandra made few friends growing up, one of them being (she didn't know yet) a satyr named Michael. As she grew up and started to go to elementary school, her mother's drunkenness was further coupled with neglect and Cassandra would often be simply left alone, though her mother would either cook her meals or buy takeout occasionally. Cassandra experienced a lonely, abusive childhood and never got to do things that other kids did with their families (such as skating).
One night, after Cassandra had received a particularly harsh beating from her mother and had gotten drunk afterwards, (at the age of 12) she had called Michael to her house so that she may escape. Upon this, Michael explained that he knew a safe place and proceeded to initiate her into the world of the Gods. She initially refused to believe the story but later did after Michael discovered the amulet and letter from Aeolus hidden under a loose floorboard. Upon reading it, Cassandra agreed and they left for Camp Half-Blood. On the way to Camp, they were ambushed on the road by Scythian Dracanae (God forbid I forgot how to spell that). Splitting her amulet in half, the two pieces elongated into a long chain, with two scythe-like, Celestial Bronze blades at the end. Accidentally jerking her arm up to protect her face, the weapon arced upwards, slicing one of the monsters from toe to head. Opening her eyes, she saw the monster vapourizing into dust and she gained confidence. The snake women charged her but she swung both kusarigama clockwise, twirling in a deadly dance. She vapourized three more before wrapping the chain of one of her weapons around the last, immobilizing it-her. She pulled and brought the monster closer before using the blade of her weapon to disentagrate it into dust.
They arrived safely afterwards and she was immediately claimed by Aeolus. She spent the next seven years honing her skills as a fighter, developing a talent for the mixed martial arts as well as using the dual kusarigama and dual celestial bronze cleavers. She also made new friends, among which included her best friends Aeya, a daughter of Athena, and Marcus, a son of Hermes. They fought well together and knew each other's strengths and weaknesses and each other well. At the age of sixteen, the three of them decided to leave Camp to hunt monsters. Cassandra and Arya had received invitations from the Hunters of Artemis but had refused. The three of them set out for the next three years, perfecring the art of hunting monsters. Cassandra became a good huntress, good at using terrain and the shadows to her advantage. She became good at using a combination of fast but effective long and short range attacks. However, one night, they were ambushed in some alleys and in the ensuing fight, both of her friends were surrounded, overwhelmed by shear numbers, and killed by a large gang of Laistrygonians. She managed to escape and fled back to Camp Half Blood, bitter and cold (in her heart). She later changed her last name to Athenas, in tribute to her dead friend's god parent and so that she would no longer be related to her biological mother. In addition to her power handicap, she is also known to passionately hate monsters and can quite often go into a murderous frenzy, unable to distinguish friend from foe. She receives no additional benefits from this frenzy. She is now 19 when she reaches Camp for a second time.