Roxanne is small for her age, with a slight delicate frame that makes her seem younger than her age. Her hair is naturally blonde, and her eyes are a striking crystal blue. Her skin is almost porcelain-pale. She looks remarkably like her mother.

Roxanne is sharp and quick witted. Her humor is dry, and often cutting, and she uses it as a shield. First impressions don't usually go well with her, as she can come across as prickly or standoffish to those who don't know her. She has a hard time letting people in. However, once you earn her trust, she is a fiercely loyal friend.

Roxanne's mother was a witch who found she couldn't commit to a life tethered to the muggle world, or to the family she started, and left when Roxanne was five. She was raised primarily by her muggle father and stepmother. Her relationship with her father is loving, but distant, as he can't help but see Roxanne's mother every time he looks at her. Her relationship with her stepmother is cordial at best, lacking any real familial love or warmth. She has two younger half-brothers from her father's and stepmother's marriage. She loves them, but she's not very close with them. Growing up, she had a small circle of friends, but always felt removed from them in some way, like she was slightly different from them.

Her first instance of wandless magic was when she was six years old, standing in her bathroom, staring at her reflection in the mirror. Her father had made a comment about how looking at her was painful because all he could see was her mother. Upset, Roxanne screamed and cried, and suddenly, the mirror shattered into shards right in front of her.