A or B? Sorry, I’m Tearing Up This Plot

I took part in a game where I had to kill myself. Welcome to the game we play together. [Slow-growing heroine who goes on a rampage once she figures things out.] [One woman vs. three men. Who is her destined love?] [No. I'm my own one and only, my own destiny.] Who knew the biggest pitfall of transmigrating into a book would be the System! Wait, what other traps are waiting for me? Solve cases? I can learn! Fight bad guys? If I can't beat them, I can find someone powerful to back me up? Wait, how did I become the one everyone relies on? Huh? Wait, why is this System imitating me? Is the System assigning missions, or am I the one giving them?