Another theme could be privacy itself. It may show how the sister tries to protect her private space and what happens when that privacy is invaded. It could also be about self - discovery. The sister may be on a journey to understand herself better in her private life, away from the outside world's expectations.
There could be a theme of secrets as well. Maybe the sister has some secrets in her private life that she is either trying to keep or is forced to reveal. This could create drama and tension in the story. Also, love and romance might be a theme if her private life involves relationships with others, and how those relationships shape her personal growth and privacy.
One possible theme could be self - discovery. As she navigates her private life, the sister might be on a journey to understand herself better.
I'm sorry, I haven't read this specific novel. It could be about the private and personal experiences of the sister character, perhaps her relationships, dreams, or secrets.
One possible theme could be devotion. If a wife is considered as one's life, it implies a high level of commitment and loyalty. Another theme might be the significance of the relationship in shaping one's identity. Since the wife is equated to life, she probably has a major impact on who the person is.
Another theme might be the passage of time. As the story unfolds, we could see how time has changed the character, their relationships, and their view of the world. It could also touch on themes like resilience, as the character overcomes various difficulties in their life journey. For instance, if they faced a tough childhood but managed to build a better life for themselves later, that would show resilience.
One possible theme could be self - discovery. In a mysterious life, the main character often has to figure out who they really are.
Love and loss could be themes. There might be relationships that are affected by the twists in the character's life. They could lose someone they love or find new love in unexpected ways. Also, the theme of fate or destiny could be present. The twists could be seen as events that are meant to happen, guiding the character's life in a certain direction.
Survival might be another theme. In a world where she has such a lethal ability, she may need to use it to survive against various threats, whether they are other characters, monsters, or a hostile environment.
One possible theme could be the struggle for self - identity. In a ruined academy life, the main character may be constantly trying to figure out who they are among all the chaos. Another theme might be the importance of friendship. Despite the ruined situation, true friends could be a source of support.
One possible theme could be friendship. Since it involves a big sister and a game, they might develop a deeper friendship - like bond through the play. Another theme could be adventure, if the game is about exploring or going on quests.
Love and self - discovery are often main themes. In many novels about private lives, characters explore their own identities and desires, and love, be it romantic or platonic, plays a significant role in this exploration.