Harry woke up to darkness.
The castle stones were cool to the touch as he quietly made his way around the corridors. Broken stones littered the floor in places, he had to carefully plot his path to avoid them.
It wouldn't do to rouse those still asleep.
He hadn't intended to start these morning walks; changing his sleep schedule so drastically. But sleeping for more than 24 hours after the Battle of Hogwarts had ended would have that effect on most.
Harry just wanted to avoid everyone right now. The hours after the fight and the grieving that had followed exhausted his emotions. And as his friends continued their wake, he had taken to avoiding them.
He hadn't wanted them to see his inability to truly be sad. Maybe it was the fight with Voldemort which had left him bereft of feelings, or maybe it was simply the sheer number of losses he had already obtained over his life, but he knew that something was wrong with him when he continued on as normal.
These thoughts had been repeating in the past week, mostly when he took these walks of his. It took far too much effort to avoid interaction with friends and new followers to allow himself stray thoughts then.
Hence, the walks. The walks until dawn when the castle woke up and began their day of rebuilding. When he took to hiding in empty classrooms and broken corridors and weird sleep schedules.
To prevent everyone from finding that he was broken, and wasn't sure how he could be fixed.