Joseph Sims has blonde hair, is relatively handsome and has dark brown eyes and a relatively round face. His skin is a darker shade if beige and he has a small nose. He is generally above average in terms of height but is underweight for his age.

Joseph Sims is a loyal companion that would stick through his friends through thick and the thin, but he values nothing more than his academics and results and would settle for nothing less than first in any competition. He also cannot bear to turn down a challenge which often gets him into trouble.

Joseph Sims grew up in a family of wizards and witches, and has a younger sister and an older brother, who has already graduated from Hogwarts. Being overly competitive, he often quarrelled with his siblings and thus hated them. However, he loves his two muggle friends that he meets up with everyday to have lunch and have fun.

A month ago, Joseph Sims had returned home after a long frustrating day as he had lost his wallet, which contained many of his most treasured items, so when his little sister approached him to ask for a new pen he was extremely irritated and without knowing he caused the entire dining table and all the dishes on it to suddenly levitate and speed towards the younger sister. Thankfully she managed to dodge the table and dishes in time and was not seriously hurt.