Day before the 1st day of Xmas

By some mischievous being, magical advent calendars started to pop up around the world, some looked full, while others would have some of the days missing already from them, however if someone at the right time was drawn to the calendar as if called by it, and they opened up the earliest day on their little calendar. The calendars were all connected, so each person called would be opening they day they were meant to find and open. 

All the while in the shadows, able to watch events unfold was the being, a smile on his face, he knew that the people who would be called would forever be changed by the calendars.