An apprentice magician finds out one day that the wizard to whom he is apprenticed has captured two spirits, a demon and an angel, in two separate crystals.
When he asks his master why, his master says that he has tired of human knowledge, and wants the enlightenment of both heaven and hell. When his pupil asks him why he captured the demon and not just the angel, he replies that there are truths heaven is too uptight to unfold, and hell is more than eager to reveal.
Over time, the wizard is told little by the angel, but much by the demon, as the angel focuses on explaining each holy truth to him, but the demon explains all manner of unholy secrets that the wizard gains nothing from knowing. Over time, the wizard, because of this exchange, considers himself more enlightened to a ‘truth’ about reality that he has decided to believe, that goodness is a narrow section of experience, but evil is a great, wide, open world, full of freedom.
Because of this, the apprentice watches his master become more and more corrupted, delving into the darker magics, and beginning to conjure more demons. Only in his sleep is the apprentice’s master not the increasingly intense beacon of terror that he is in his waking hours.
The younger magician, who knew nothing of what either spirit told his master, had not been deceived by the demon, and saw his master for what he truly was: A man being corrupted into something akin to a demon himself.
The young man, terrified of his master, could not sleep, because, as his apprentice, he had to sleep in his master’s room. But one day, the wizard, swearing his apprentice to absolute secrecy, told the young magician that tomorrow they would have to find a young virgin, and kidnap her, replacing her with a solid illusion that would act exactly as she had, by receiving information across timelines as to how she would act.
The apprentice silently refused to let himself be corrupted as his master had been, and so on that night, the student pondered how he could stop his master. Though he thought of complex stratagems, magical means of imprisonment, and even various curses, a simpler solution came to him, in the form of a loose brick in the wall above his master’s bed. Weaving a simple telekinetic spell in his mind, he pulled the brick out of the wall, and dropped it on his master’s head.
As the magician made sure his master had died, the angel’s crystal lit up, as the being spoke, beckoning him forward, to receive the last revelation that his master would have, had he not become too corrupted to be turned around. The revelation was this:
If good seems like a narrow road, that is because perfection requires many virtues, and each virtue can be lacking in many ways. Thus, a whole world is formed of the many forms of vice of which one can be guilty. But freedom to damn oneself is only valuable as a means of legitimizing the value of one’s virtue; if vice is possible, then virtue is chosen where it exists. The world of evil is not a world to be explored, but rather to be escaped, as it is the world into which we are born.
So yeah, it has magic(so it’s a fairy tale), at least one morbid death(so it’s like a Grimm’s fairy tale) and a moral at the end(which should probably be condensed, should the story be written, so it sounds less like a letter C.S. Lewis would write)