Two Souls, One Door: Another Realm

How do you leave a room when the only door disappears and reappears at random, and moves away from you when you approach? How do you leave an endless void of darkness and silence? And when the only rule that governs the room is only one person may pass through the door?

For Rebecca and Carter, leaving the void has an added complication: a creature of light stalking their every move. It encircles them, hidden by the vastness and darkness of the void, and striking without warning.

For one of the souls within the void is an anomaly.
One of them doesn’t belong.

And only one of them can walk through the door that will eventually open.