I was running. There was nothing I could do but run. A giant monster, at least ten feet tall, dark crimson, and with six glowing eyes was chasing me. It had a giant sword that it used to cut down everything in its way, and whatever it cut bled a lot, even things like rocks and the ground. The sword also sent out a spray of blood whenever it was swung, and whatever the blood touched started to rot and fester. When the rot was cut, large chunks of flesh exploded outward. I even saw the monster catch and eat one of the pieces without pause.
I've ran through Canterlot, Ponyville, and am currently running through a thick forest. I am sore all over and out of breath, yet I have to keep running.
I saw a white glow up ahead against the red-orange sky, and aunt Luna appeared. Finally, I was safe. I stopped a short distance behind her and plopped down on the ground. I looked back the way I had come and saw a thick mass of branches where I had come from, aunt Luna facing it. Seconds later, the bleeding sword cut through the branches with no problem and the monster followed with even fewer. It saw Luna, who fired a bolt of magic at its head. Despite the direct blow, the monster was unfazed. With its free hand, it grabbed aunt Luna's horn and snapped it off with a sickening crack. Before she could do anything else, one of her wings got cut off by the giant sword, along with part of her ribs.
The monster grabbed Luna's neck just under her head, its fingers breaking her skin and making her bleed. Then, in a deep voice, it spoke. "I am Chimatsuri Dokoku, the incarnation of fear."
"Get out of my niece's dream, demon" Luna ordered. She tried to cast a spell, but all that happened was blood spraying out of her broken horn, some of which landed on the monster's face. It opened its mouth, and a tongue far too long for its head licked some of the blood off. "Delicious. I've never tasted blood this exquisite before. I want more, now."
The monster tossed aunt Luna up in the air before slashing her with unnatural speed, cutting her into large chunks, which hit the ground shriveled up, drained of all blood. Her head rolled towards me, bits of the skin falling off as it came closer. When it stopped, it looked like a patchwork of bone, muscle, skin, and bits of eye all over.
I was too tired and stunned by what I saw to do anything but see the blade, dripping with blood, falling towards me.
I woke up screaming and breathing heavily, covered in a cold sweat. A minute later, mom came in to comfort me.
"Shh, Inova. It was just a dream. It was just a dream" she whispered. I cried into her fur. I was still so scared by what I saw. I tried not to fall asleep. During one such effort, I heard mom mention how Skyla was still asleep despite what just happened.
Luna woke up from her dreamwalking screaming and breathing heavily, covered in a cold sweat. A few minutes later, Celestia entered her room.
"Luna? Is everything alright?" Celestia asked. She looked around the spacious room and saw Luna cowering in a corner, huddled and shivering in her blanket, fear on her face. Celestia drew closer before kneeling down and asking again. Luna's eyes never moved.
"Demon. Blood. Giant sword. So much pain. Dissection" Luna said, clearly unable to form full and proper senses.
"Was it somepony's nightmare?"
Luna just nodded, still staring straight ahead.
"Can I see what you saw?"
Luna nodded again and cautiously lit her horn. Once the spell was going, and it was evident Luna wouldn't move, Celestia put her head against Luna's horn.
Over the next fifteen seconds, Celestia experienced everything Luna had in the nightmare, though it felt like hours had passed once it was over.
During the fifteen seconds after seeing the nightmare, Celestia wormed her way into the blanket and huddled in fear with her sister.
After fifteen minutes huddled together, the royal sisters had finally calmed down. After ordering some hot cocoa with a practiced spell, Celestia was the first to speak. "Whose nightmare was that, Luna?"
"It was Inova's nightmare" Luna said, disbelief in her voice.
It took a moment for that to sink in for Celestia. "Inova? As in, the same Inova that we are aunts to?"
"Yes, her. I don't know what could have inspired such a nightmare, especially one of such detail."
"Should we tell Cadence of the demon?"
"I don't know, 'Tia. On one hoof, it would let her know just what scared Inova. On the other, well, look at us" Luna motioned to herself and Celestia, still wrapped up in the blanket and huddled in the corner.
Moments later a knock sounded from the door. "Your hot cocoa, Princesses" a maid called.
Celestia cast an illusion and opened the door, appearing to accept the hot cocoas right at the door. "Thank you. Have a good evening" Celestia said.
"You too, your highnesses" the maid said before leaving. Once the door was gone, the illusion also vanished and the hot cocoas were quickly brought to Celestia and Luna's lips, the sweet, warm chocolate drink helping soothe their nerves.
"I think we shouldn't tell Cadence" Luna said.
"Oh?" Celestia asked.
"I think the only ponies who should know the details of this nightmare are you, me, and Inova. Any more, and things might get out of hoof. It could even induce a whole slew of nightmares among our ponies, and that would mess up everything for them. This can't be known to anypony else, not even Cadence."
"You make some good points there, Luna. But why shouldn't Cadence know?"
"Have you talked with her when she's sleep deprived? She says things that should be secret. Sharing the nightmare with her would probably put her in such a state, and she'd probably slip the nightmare out."
"Ah. Now that that's settled, do you want me to sleep with you tonight?"
"Gladly, sister. But I have one condition" Luna stated.
"What is it?"
"That we finish the hot cocoas and talk about better things first."
"Oh, your demands. They are so unreasonably reasonable" Celestia overdramatized. "I bow to your conditions, Princess of the night."