Prynne look like an average seventeen-year-old girl. She can be considered tall, though not as much as Nathaniel. While not exactly malnourished, she is actually considered quite underweight due to her eating habits. Much like her brother, she sports blueish-silver hair and turquoise eyes. Her hair is kept long, reaching her lower back when it is let down, though it is usually kept up in a ponytail at the left side of her head. She's dressed very similar to her brother as well, wearing a knee-long black dress with a white sash tied around the waist in a bow, and a black turtleneck shirt underneath, as well as black knee-high socks, and cream-coloured shoes. She wears a silver cross, twin to the one Nathaniel also carries. She is never seen without it as it was a gift from him for her 16th birthday. The most "colourful", distinct feature about her attire is the hair ties that she chooses to wear, usually being very bright in colour (her favourite ones being teal and sky blue).

Prynne is a shy, usually quiet girl. She is not hard to get a smile out of, but due to her traumatising and secluded childhood she is scared of meeting new people and often doesn’t fare well in social situations. She stammers a lot when around strangers, or during anxiety-inducing situation, and is very fidgety and worrysome. However, as soon as she opens up to someone and befriends them, she's shown to be a kind, compassionate individual that always strives for the good of those she loves. Unfortunately for her, she is way too trusting and will always try to see the good in someone, which may often land her in trouble.

She is very attached to Nathaniel, who's essentially her only family and her best friend. She hates being away from him and will follow him anywhere when she can, also worrying about him most of the time. She always wants to be able to help and support him, even when he shuts her away for her own good. As she was brought up largely by him, Prynne shares his strong beliefs and often judgemental character, when it comes to religion; she puts great weight in her faith in God, and while she believes all must be given a second chance, she will be swift to agree in the deliverance of punishment should she judge it to be needed. Additionally, she's shown to be extremely stubborn and not give up easily at all, especially when it comes to keeping her brother safe.

Due to the (admittedly limited) memories of her childhood, Prynne suffers from severe guilt complex. She believes that the death of hers and Nathaniel’s mother to be her fault and, consequently, blames herself for every ill situation that’s befallen her brother ever since then. As such it is easy for her to be guilt-tripped and manipulated by others who may seek so, and will be swift to blame herself for whatever tragedy befalls her loved ones.

Due to the aforementioned reasons, she suffers from crippling separation anxiety, to the point where she cannot bear to be alone for prolonged periods of time, and will constantly seek company, mostly that of her brother. Her condition is serious enough to the point of her being unable to function alone, losing appetite, sleep, etc. when she’s not in the company of someone. That often makes her extremely clingy and dependent. Consequently, she gets attached way too easily to people and is a terrible judge of character. While she will settle for the company of anyone if she's desperate, most of the times she will only be fully comforted by the presence of her brother, and being kept away from him is essentially torture for her.