I Belong to the Queen Mother, but I Became His Queen

I was sold into the palace. The clan said they were sending me to serve the nobles, but in reality they wanted me to serve as the Queen Mother's eyes, keeping an eye on the sickly young emperor. On my first night in the palace, I was involved in a fatal poisoning and murder case - the person who died was the newly appointed concubine, but the blame was placed on me. The days in the palace are one step at a time. I just wanted to wait until I left the palace and die of old age. But every time I wanted to retreat, someone would push me forward: push me to die, push me to block the knife, push me to be the most eye-catching target. Later, I learned my lesson - since there is no way to retreat, I will go forward and kill. Fight your way to that position. But when I finally sat in that position, I realized: I thought I was taking revenge. It turns out that this palace wall, from beginning to end, was his plan for me.