Mimir

This Stygian was born from a life whose stress bordered the line of dramatics. Days would drag themselves on to eternities, and the life would be stuck clawing and biting just to get through to the end. The brief silver linings would quickly be swept away by enormous, brooding thunderclouds gathering on the horizon, bringing an even more intense bout of rain. Their only solace was sleep- in which they could safely explore their wildest and craziest fantasies without repercussion, and live a life more wondrous and hopeful than their waking one. However, the moment the alarm rings, the dreams fade, and they're stricken by the cold, harsh slap of returning to the real world, and the dread starts anew. Thus, a cycle was born- the life would claw and bite through the day in a struggle to get to their bed, so they could cloak themself in darkness and travel to their happy place before they were torn away and dragged back to the start. And in this cycle, it is one sunrise in particular that also gives rise to an intrusive thought that changes them forever.

Being asleep is easier than being awake.

Should they sleep forever? What if they chose to never awake again? Wouldn't that be fun? But they couldn't, they still had too much here. ..What if it really WAS too much, would they try to end it all? They've thought about that before, haven't they? Now, not only do they live in dread of the day, they live in the dread of what they're capable of if left unchecked at night.

Thus, the fantasm of dreams simply vanishes. Thus, a nightmare of how alluring those dreams are formed in its place.