Sumia is a klutzy individual, prone to small mishaps. In fact, her clumsiness is so bad that she trips over nothing more than anyone in the Shepherds, much to her embarassment. Because of this, she feels that she is sometimes unsuited for her job but still does her best whenever she can. Despite her clumsy habits, she holds a hidden strength that most people lack. She has a strong affinity for animals and can read their feelings very well. She used this ability to calm and tame an injured pegasus that was feral to everyone else. Even a horse that Frederick could not tame was quickly quelled by Sumia. Her best friend is her fellow Pegasus Knight Cordelia, who is always there to help her when she is in trouble, and admires her flawless demeanor. Still she has shown to be courageous, caring, and kind, willing to fight for her people.