"Um..." she has to think about it for a bit, trying to figure it out, "Self-defense is pretty much a compulsary course in Gotham schools, but I didn't start doing it properly until I was about fifteen. So four years ago. It's been on and off since then."

Mostly because her teachers would abitrarily decide they were going to abandon her every now and then. Cass was probably the most consistent teacher she ever had, "A fair bit of it's self-taught, I guess."