(This is basically a backstory-)
Memory used to live a really happy life, that is, until when she was about 7. Her clan needed food, so they sold her to experimenters. Thats how she got the face different from her old face. They would always poke and prod at her and jab needles into her side and face. Because she would always kick them and yowl, they would hurt her. Sometimes they would even cut off small chunks of her leg. Thats why she would always fall, even without the lights. They would always make her suffer more and more until she had enough of it. When they let her out to actually explore, she killed them- after that, she ran off into the forest and hid in a giant tunnel underground so that when something attacks, she can run around in the tunnels and get away.