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The bedrooms the boys usually slept in were close to his chambers but not right next door. They were in the same hall, just further down and clustered together. They chose them like mildly rebellious teenagers who wanted to strike out on their own while only moving a block away. With them currently being so small, Nightmare didn’t want them even that far away. Besides, their rooms were far too much of a mess as well. (Except for Cross’ room, but that is beside the point.)

No, Nightmare wanted these younger versions of his boys closer to his room and in a cleaner space. Also, with how clingy they were towards each other, they would be best all together in one room versus separated in four different ones like normal.

So he picked a room right next to his. While Lyra got them washed up for the night, he got the room ready for them. Their favorite blankets he did fetch from their rooms with pictures or other items each boy seemed fond of. They might not remember these objects, but if those items bring any amount of comfort, then the effort is worth it. As he was doing this, it was starting to hit him.

Obviously, he knew and understood what happened, but all this time, he had been reacting to the situation. He did ponder it before… but as he was setting up a room for them, the realness of this was sinking further in. He sat on a chair he set near the bed to read from as he needed a moment to settle the complex feelings within him.

This evening had been nice. They ate dinner together, played a board game, and enjoyed each other's company. But the fact is that his boys were different. As enjoyable as this afternoon and evening were, he wanted the adults back. He even missed the chaos of them. He would know they were alright if they were their true selves again. Additionally, they would know who he was and not be wondering why they couldn’t go home.

(Except for Dust, that one could use being raised by him. A far better option than his actual childhood.)

But even the adult Dust he sorely missed.

“Here we are!” Said Lyra as she guided the boys into the room. They were all dressed for bed and looking around with wide, bright sockets.

“wow! we get to sleep here?!” Killer asked as he looked up at Lyra.

“Yes, you do! It is the room Mr. Night chose for you to sleep in. Was that nice of him?” She asked.

“yes!” Cross replied as he then ran in and over to the bed. 

It was a tall bed, so Nightmare had put a step stool for the children to use. Cross, though, being the adventurous child he is, decided to disregard the stool and try climbing up on his own. The heavy emotions Nightmare had been feeling were replaced by amusement as he watched the child struggle to climb up to the top.

“Do you want help, Cross?” Nightmare asked.

“mm, nah… i got… it,” Cross huffed as he finally squirmed and pulled his way up.

“oh! I wanna try!” Killer said as he started climbing.

Horror used the step stool and then helped Dust up as well. They sat on the bed, watching Killer struggle his way up and join Cross in laying on his back and catching his breath.

Breath finally caught, Cross sat up and smiled at Nightmare, “thank you, mr. night!”

“what… he said,” Killer wheezed.

Horror and Dust also said their thank yous, though Dust’s was more mumbled than anything. He picked up one of the books Lyra had previously bought and opened it. The story was very… simple… so was the wording. He frowned for a moment and then looked at the Toriel in question. “This is really meant for children?”

“Well… yes,” She replied, looking confused.

“There is nothing here to challenge the mind,” He stated with a frown.

“They are getting ready for bed, not school. You can read something to offer a challenge in the morning. For now, a simple story, with a simple moral, is best for sleeping,” She explained, and Nightmare had to admit that made sense. Still, he had been reading far more advanced books when he was just a little older than them.

“i wanna be challenged!” Killer protested.

“what kind of challenge?” Cross asked as he sat up. “is it a test of strength?”

“or speed?” Killer asked.

“It is a test to see,” Lyra started, but Nightmare could see the nervousness in Dust’s eyelights.

“Not a test,” Nightmare said quickly to cut off. “Also, no challenges tonight. What Lyra was saying is right. You four need sleep.”

“but i don’t wanna,” Killer huffed.

“Well, if you do not sleep, then you will not be able to do anything fun tomorrow,” Nightmare stated flatly.

“what?! why not?!” Killer then demanded, sitting up, “that’s mean! why won’t you let me do anything fun tomorrow just for not sleeping?”

“It will not be me not letting you. It will be you being too tired to do anything fun,” Nightmare replied. He then mused and set the book aside. “I think I have the perfect story for the night. It is one that actually happened, and I was there to see.”

“Did it happen last week?” Killer asked.

“Longer than that,” Nightmare replied.

“Last month?” Cross then asked, wanting to join in this game.

“Longer,” Nightmare answered.

Horror was now curious and spoke up, “two years ago?”

“Still longer,” Nightmare replied.

“how old are you, mr. night?” Dust asked quietly.

“I am both very old and not at the same time,” Nightmare answered, “Now, will you let me tell my story?”

“how can you be very old and not very old?” Killer asked.

“are you like the boss monsters? they stop aging unless they have kids.” Horror asked.

“We are like that, yes,” Lyra replied. She then smiled at Nightmare. “I will go clean up and let you tell your story.”

She left the room, and he stood and readjusted the blankets. As Nightmare tucked them each in, he started his story. “Settle in, comfy cozy, as they say. Now, once upon a time, a very long time ago, there was a tiny sun and a tiny moon. They were brothers, and they got along very well, sharing what they had and protecting a great planet that was their mother.”

Killer gasped quietly and whispered, “i love space!”

“shhh,” Replied Horror.

“Now the sun was always bright and happy, and all the mortals that lived on their mother were happy to see him. They were so glad to see him that one day, this tiny sun asked if he could stay up with his brother, the moon, all night long. The moon wasn’t sure if that was wise and asked the sun if he would still be able to warm the planet the next day if he did that. Too excited to think about the consequences, the sun assured the moon he could. That night, the sun played all night with the moon, and the moon had so much fun playing with his brother, the sun.

“Then the morning came, and the sun was so tired that he fell asleep. Worried for his brother, the moon tried to help, but his light wasn’t as strong as the sun’s. The mortals became cold, and that made them angry.”

“Moon!” Nightmare snapped in a more gruff voice. “Where is Sun? We need him, not you!”

The next voice he did was more youthful, and he felt odd hearing it. Still, he continued, as the children seemed happy, “I am sorry, cried Moon. I am trying my best, but my brother is tired and needs to sleep. I will help you the best I can.”

“It is your fault! You tricked him into being active at night when we need to sleep. Now, when we need his light and warmth, we are in the dark and cold! The mortals yelled at the small moon. They continued to insult and threaten the moon until he ran and hid. Soon, the sun woke, and he saw his brother was gone.”

“Sun! The mortal called, We have chased off the wicked moon who dared to steal your place.”

“This surprised the sun, and he then ran. The mortals yelled after the sun as they were left in darkness without Sun providing his light. They did not even have the tiny moon there to give his light. Still, that did not matter to Sun as he wanted to find his brother, Moon. So, he left the mortals in their darkness.

“He searched and searched, finding the small moon eventually by a stream of stardust. He apologized to the moon for breaking his promise and said that he would do his best to complete his duties so the mortals would never talk to him like that ever again.”

“did the moon forgive him?” Killer asked.

“Yes, he did,” Nightmare answered.

“the mortals should have apologized!” Cross frowned and folded his arms.

“what are mortals anyway?” Killer asked.

“i don’t know what they are either,” Cross frowned.

“None of you know what mortals are?” Nightmare asked. And all but one shook their heads. “Dust?”

“they… are any creature that can grow old and die…,” Dust said softly.

“That is correct. Humans and monsters are all mortals,” Nightmare praised.

“are there things that don’t?” Killer asked, looking at Dust.

“immortal is the word for a thing that doesn’t grow old and die,” Dust answered.

“Well done,” Nightmare nodded.

“are you in-mortal?” Cross asked Nightmare.

Killer then gasped and sat up, “is that how you’re old and not old?”

“It is pronounced immortal, but yes,” Nightmare said before he had Killer lie back to tuck him in again. “Now, we can discuss this more in the morning. Good night.”

He reached over to turn off the light when Killer whined, “don’t we get a kiss goodnight?”

“A what?” Nightmare frowned as he looked at Killer.

“dad always gives me a kiss on the head right here,” Killer pointed at a spot in the middle of his forehead. “i can’t go to sleep without it.”

“What do you mean you can’t? You did last night,” Nightmare corrected.

“that was a slumber party, that’s different,” Killer whined.

“Is this not also, in a way, a ‘slumber party?’” Nightmare frowned.

“nuh-uh! this is different,” Killer frowned and folded his arms.

“slumber parties have games, and you stay up late and watch movies and stuff,” Cross explained.

“this is ‘mommy and daddy wanna do fun stuff without the kids, so we have to go to bed when they want,’” Killer huffed, and Horror snorted back a laugh.

“what?! what kinda fun stuff do they do?” Cross said while looking shocked at the idea that what Killer said could be true.

“stuff that isn’t even fun, like kissing,” Killer complained.

“If kissing is an issue, why are you asking for one?” Nightmare inquired.

“it’s diiiiiifferent!” Killer threw his arms up as he spoke with an exasperated tone. As annoying as this was, Nightmare could not help but find amusement. “i want a bedtime kiss. adult do gross mouth kissing!” Killer frowned and glared at the ceiling as he folded his arms again.

“ewww, do they brush their teeth first?” Cross asked.

“i don’t think they do since they just kiss each other on the lips. or teeth for skeletons or non-lip monsters,” Horror added.

“nuh-uh! i saw some kissing before, and they were opening their mouths and-” Killer started.

“That is enough,” Nightmare interjected as this was getting out of hand. He highly doubted he would hear the end of this if he didn’t surrender to Killer’s demands. “Here,” he said as he bent over and kissed Kill’s forehead. Then he did the same for Cross, Horror, and Dust. “Now, go to sleep.”

“thank you, and good night, mr. night!” Killer said with a big smile before rolling to his side and closing his sockets. The others added their own thank yous and settled into bed to sleep. Nightmare turned off the light and then turned to leave. The cartoon-style dragon night light illuminated the way, even though he didn’t need it to see.

He stepped out into the hall, noticing Lyra was standing nearby as he closed the door most of the way. She leaned closer to him and said softly, “I thought I was going to have to save you.”

“You already have,” He smiled at her. “Thank you”

“I will ask you one more time. Are you sure?” She asked as she looked at him calmly. “My room is just right over there. The very room you gave me so I would feel more welcomed here. I can stay… I will stay however long you need me.”

He looked away, thinking about that. If there was no cure? What then? She would be stuck being the mother of his sons… his henchmen who would truly be his sons. No. He knows Toriel’s are motherly, but he highly doubted the boys sleeping in the room behind him were the type of children she would want to be the mother of. If he lets her stay, she will accept that fate… just as she has allowed him to cling to her.

“Lyra, I will call you when I need help, I guarantee that. But let me at least try,” He said.

She hummed softly and nodded, “Alright, I understand. They are your boys.”

Lyra then did something he did not expect as she placed her hand on his face, along his left jawline. She directed his head to tilt up as she leaned down and gently kissed his forehead. “Good night, Moonbeam.”

He blinked at her as she pulled away and gave him a mischievous smile. All the while, his mind struggled to get caught up with the act that just occurred. It took longer than it should have to register that she kissed him good night.

Not once in his long life had he ever been kissed goodnight before. And now…

Her portal was open, and she was walking towards it. His mind snapped out of its daze just in time for Nightmare to say, “Good night, Lyra.” She gave him another smile before walking through and leaving his castle.

…

Nightmare should go to his office, where he stashed the dating advice books. He was not as ready for that as he should have been. It was such a… soft and platonic kiss that it should not have startled him. Leaning against the castle wall, he sighed… it was likely just him being tired and honestly not used to acts of affection beyond initiating hugs with others.

He needed sleep… and while the boys were asleep, he should sleep too.

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