Doomsday: Perfect Experimental Subject

In the last year of the world, the city is filled with corpses. My sister and I were captured by the base and used as experimental materials. When we were about to die, we awakened to devour the system. I evolved and became stronger along the way, and the entire base regarded me as an out-of-control aberration. There is only one person I want, my sister. But the price of increasing strength is the constant loss of humanity, and I am ultimately trapped in other people's experiments.