King Sombra is many things. He is a monster, he is a terrorist, he is the cause of war, he is a cruel, heartless tyrant only waging violence and the death of so many ponies for his own gain. And he knows this.
However, what he didn't know, was that he was slowly falling for a specific pony. One of his most loyal subjects. She works as the second in command of the empire, a scientist and a librarian. But she is no doubt a special mare. King Sombra had not a clue, though, that she'd be special enough to make him feel this way. He can't comprehend it. He tries to comprehend it. It feels both good and painful.
Note: A story idea I had for a long, long time. I wish to turn it into a full story someday.
Second Note: The events of this story take place in King Sombra's timeline from the season 5 finale.