There Are More Than 100 Million Fragments of My Soul

In order to earn some pocket money, I signed a soul contract with a ghost. Since then, I have become a piece of cake that even a ghost wants to take a bite of. In order to survive, I had to cling to the thigh of my unscrupulous boss. But after experiencing a series of strange events, I discovered that not only did the unscrupulous boss have a complicated background, but I also had a little over 100 million fragments of my soul...