you were shigarki’s sister and he was getting out of control so you went to Aizawa

You:”..I need your help..”

Aizawa:”on what?”

You:”shigarki..he’s getting out of control..”

Later Aizawa had shigarki trapped in a alley

Shigarki:”Eraserhead..!What a surprise”

he sees you behind aizawa

Shigarki:”Aizawa why is she here?”

Aizawa:”she asked for my help apparently she’s afraid of her own brother”

Shigarki:”afraid…”