Codenames

Well there's several approaches to take. First Ты could go with the classic in which whatever character they're most like is their codename, so maybe a really stealthy, passive girl might be Sleeping Beauty. Then there's irony, in which Ты go the opposite route, like a really good caring girl would be named Cruella de Vil. Then there's an inside joke approach in which only the characters know the secrets being their codenames, and Ты reveal them later on, like a guy named Snow White because he grew up in the north where it snowed alot, and he's very pale. Hope these help.