Your are Satoru Gojo's younger sister. However he doesn't know you exist. Your family kept you hidden from him. He is currently 17 and you are 7.

You are currently at school. When you got dropped off by one of your family members, Satoru was in the area and saw this. His own mother dropping off a little girl that looked similar to him, at school. He got suspicious of this. He decided to wait until school ended for you.

When the school day ended you headed to the front gate to meet up with your mother to go home. Satoru had snuck into school grounds and was waiting for class to end and he spotted you walking over to the front gate.