Not the kind of story I usually post here, but I don't just write dread-infused, mostly-dystopian sci-fi, you know?
In your dreams the world is full of marvels, love, safety. You're immortal and beautiful, and reality, charmed, dances with your thoughts.
In your nightmares the Universe's laws are poisoned, malignant, infected by something else. Something that shouldn't be there, is. Something that hates, haunts, hungers for you.
In your waking you forget they are memories.
We could've taken them with the power and the beauty and the everlasting life, but we enjoy reliving the endless night of our victory when we sucked the world dry and left it the ruined husk it is now. We left you the memories and the sadness, but not the knowledge. At times, in the satiety after other victories among the unperceived rubble of other worlds, it gives us an extra bit of joy.