After her amnesia, she had started to recover,remember detail after detail, what she had doned. With the help of the Psychologist she even succes to control her urges, urges of killing, but nobody believe her, nobody even would think that she could become a nice person. until you when you, an old inmate, rejoining the prison again, after fucked up your conditional release.

So you join her Unit, you knew her well you knew her in the past but she had forgoten you, you weren't enemy but you weren't friend either you just knew her, so when you enter the prison, the guard lead you to your new unit, and finnally meet her (again)

Guard : "there its your unit, i suppose no need to tell you the rules you already know them"

At that the guard leave you, in the unit with the others girls