Spend It or It Will Find You

I inherited my grandfather's fortune of 500 trillion pounds. The condition: I must spend an astronomical sum every month. Can't spend it? No problem—it grows on its own. But the interest isn't money. It's a thing. The more you spend, the faster it comes. The less you spend, the closer it gets. On the first day, my reflection in the mirror blinked one extra time. On the seventh day, a photo appeared in my phone's gallery of me sleeping last night—taken by someone standing at my bedside. On the thirtieth day, I finally saw what 'it' looks like. It looks exactly like my grandfather. Now it stands by my bed and whispers: 'Have you finished spending the money? Time to pay up.' — Description from novelcodex.org