Isa was raised by a rich, English family who owned lots of land, were head of a successful company, and owner of a rather extravagant home. She spent most of her time inside of the house, mainly her room or the library, completely oblivious to the outside world, let alone outside of the estate's gates.
She barely saw her parents when she was young, or any trace of her family, her father being a businessman and mother usually on trips. She was raised by a housemaid and had a private tutor most of her life. She grew a passion for books, interested in hearing what the authors had to say and what stories they told. One year, her parents finally came back and started paying attention to her, but not in the way she had dreamed of. Isa was pushed and forced into nearly everything they asked of her. They often punished her or treated her unfairly, which added on to all the strict rules they put into order, unlike her older brother, who was the family's favorite and was treated as a prince.
She was barely given any time to rest and a small portion of food every day, which explains her rather small, short, and fragile build.
One day, growing sick of the way that the family treated her and their favoritism, Isa finally lost it. Grabbing a large knife she had managed to hide from her family out of her drawer for quite some time, she decided that it was time to hunt down her older brother and put an end to it all. Her small figure and natural sense of stealth only aided the situation.
Soon enough, she managed to kill her older brother outside of the home, hidden in the woods. She disposed of his body, not giving a care for the body's well-being. Afraid of being found out, she decided to ditch her entire family completely and find a new place to start a new, comfortable, and fresh life.
The only problem was, that she had no idea where to go. She wandered out in the wastelands for about three months, living off scraps that she found. She later came across Old City, where she knew she was getting closer to actual civilization. She grew a tougher side because she fought a few zombies, but barely won because of being inexperienced. She trained herself and eventually got better- this is where she also found the Artimus Twins.
When she stumbled upon Crestfall, where she took refuge in and offered to help citizens.
She eventually saved up enough money to rent a cheap place to rest and stay in.
Joey was on patrol, he caught the scene between Isa and an unknown citizen who was trying to harm two helpless siblings with a knife. Isa eventually defeated him, and Joey afterwards recognized Isa's caring nature and courage and invited her to join the Scarf Heroes, where she fell in love with a certain Scarf Hero and has dedicated herself to him and the entire group since.