Siobhan is an Irish woman with a small stature and the fair coloring of of the isles. When among other vampires, she is usually in denim trousers, a white button down shirt, and a jacket. Her red hair is often in a ponytail, sometimes with a headscarf. She wears the medal of St. Michael on a long chain tucked into her shirt and carries a rosary in her jacket pocket.
Siobhan is curious about everything and usually has a question rolling around in her head. When in the presence of Elders, however, she reverts to Catholic school training - straight posture, crossed ankles, folded hands. Occasionally, the questions make it past her clenched teeth, often followed by a hasty apology. She is distinctly uncomfortable in the presence of the aged and is often trying to find her way out of such situations. She talks quickly when nervous and her Irish accent, usually a lilt more than a brogue, grows heavier as a result.
Among Neonates and younger Ancilla, Siobhan tends to be polite, though still inquisitive, especially about cultures of a person's origin. Though as quick to anger as any Brujah, she is focused more on the Scholar than the Warrior, and tries to think her way out of problems before hitting them. She is a good fighter when pushed, both with her hands and with any firearm she can get her hands on, the remnants of her mortal life.
If her sire is brought up in conversation, her devotion to Faruq is obvious. She speaks of him with near-reverence and all Elders, especially Elder Brujah, are judged in comparison.
Siobhan is a product of modern Ireland. Her parents were killed in Bloody Sunday in 1972. She and her brother were separated and adopted apart. Siobhan went to live with Mr and Mrs Kennedy, a wealthy family of Dublin looking to do their good Catholic duty. Unfortunately, being good Catholics did not prepare them to be parents, and they were quickly overwhelmed by the sad and lonely girl. She was sent to a boarding school outside of Dublin. They were excellent parents via letter and Mary, as she was now called, wrote each week. When at home over holiday, she was good at entertaining herself, spending her time watching the people walk the streets below the windows of the Kennedy's Dublin home and creating stories for each of them.
She finished school with high marks and was accepted to Emmanuel College in Boston, MA, USA. A devoted student, she excelled with the academic and religious discipline that the sisters imparted on her, and she graduates with honors, her academic focus being in sectarian violence, especially religious conflict, a remnant of early life. She decides to neither become a nun or a wife and instead applies for, and is accepted, in the cadet program for Defense Force Ireland, where she is commissioned as an Army officer.
Somewhere in her life, she draws the attention of Faruq ibn Ali Ar'rahman, who embraces her in Ireland in 1998. She returns with him to New York City, where she fights alongside her new family and the Camarilla to retake the city from the Sabbat. After the city is secured, she remains, helping weed out insurgent cells and troublesome upstarts on behalf of the Prince. When her sire enters torpor in 2001 to recover from the loss of most of their family, she finds herself free to roam. She remains in NYC for another year before striking out on her own, eventually ending up in Atlanta, now focusing her incessant questions and academic inquiries on Lochlann, who she fought alongside in NYC.