This door is locked

As you reach out to open the door, the Calendar throbs and quivers, its surface rippling in an uncanny, fleshy manner. A low growl comes from somewhere within and as the tip of your finger reaches the door, you feel something very much like a vein, pulsing beneath your touch. Recoiling in horror, you stumble and would fall to the ground if there were nothing to support you. But there is. Somebody is in the Calendar's chamber with you, though you entered alone. He folds you into his arms, his robe softer than fog. His beard bristles gently.

"The time is not yet right." His voice is like the cracking of thin ice on a lake and the breath that carries it smells of spun sugar and mulled wine. "You must obey the rules for the Calendar has been known to punish those who do not respect the passage of time. That is, after all, its purpose. To chronicle the end of things. The last person who pried open a portal before its time is still lost somewhere within the calendar, behind a door with no number. When no creatures are stirring in this house, I sometimes hear the scratches as he tries to find a way out, lost in the dark. Ho ho ho."

You turn to see this nocturnal visitor but there is a clattering of hooves, a cold shudder of frosty air, and you are alone in the chamber once more.

The calendar stands before you.