Sable [MHA]

A vigilante had appeared three years ago, taking on the name Sable. No one can tell their gender, or their intentions, but their irregular appearances never gave anyone the chance to pursue them. Little did the heroes know, that Sable is a teenager who was betrayed by the system.
Gunvor Mochizuki had watched as her family was killed by villains. She watched as the heroes arrived minutes later to her family having been killed by the villains they were chasing. The villains were captured and she was sent into a foster home.
The foster home had set rules, especially since she had shown no signs of having a quirk. She could not speak unless spoken to, she had to address the older kids as 'Sir/Ma'am' while the parents were addressed as 'Master/Mistress', and she had to keep the living room and dining room clean. She also had a curfew she had to follow, and her room was a closet with barely any space. She ran away and became a vigilante a year after her family died.

This story mentions things about cats that may not be accurate and frankly I don't care. It is referencing a quirk, so there is bound to be differences between real life and actual cats- big cats or just house cats.