A Generic Sanscest one shots!

Yandere Nightmare x Blue <3

Hello this story is requested by the amazing CcinoSanzUwU!

Now okay so, if you guys didn't read the title there will be yandere stuff in it that means possible stalking and or killing along with manipulation. !If you are uncomfortable with these I advise you to not read this one shot!
Now that's out of the way we'll get on with the oneshot! Hope you enjoy this! <3

Blue had been wandering around for the past few hours, not specifically doing anything but just relaxing going on a walk. It was a nice spring it was sunny and warm and it wasn't too hot and flowers had bloomed everywhere. Little did blue know that he had an audience, behind a tree nightmare had been watching blue. Following from afar had been his thing, he's basically followed blue for a long time. It doesn't quite help that he's seen where blue lives and basically knows his routines. Nightmare had been watching blue for many years, it was true. The moment he first met blue had caused this, by that time nightmare had been smaller then. He was on his way to check on his brother dream who had been hanging out with many of the other villagers. He had just gotten back from checking out a book from the library when he accidentally bumped into blue, his book fell onto the ground. Blue would pick up his book. "Hey! You dropped this when you bumped into me, also hi I'm blue!"Blue handed the book to nightmare. "Oh um..hello, I'm nightmare.." he'd take the book not making eye contact with blue. He had been shy at first when he first met blue, but little did blue know that shy little guy would eventually be overtaken by obsession.
Nightmare gathered enough courage to somewhat approach blue, blue had been sitting on a bench when nightmare sat next to him. "Hm? Oh hello sir!" Blue spoke, smiling.
He'd turn his head to face blue. "Oh- hi-" he'd get up and leave and go back to stalking blue from afar. He watched as blue went home and went to sleep, he had noticed that all of blue's friends often take up much of blue's time so he had devised a plan,a evil plan. After a couple days blue had started to notice that his friends haven't been talking with him so he'd go to see his friend alphys. Blue entered the alphys house, he had seen monster dust when he had entered. "Alphys?! Are you in here?!" He continued to worry as he walked through the house. Alphys was dead, nightmare had dusted her hours earlier and was now working his way on a bunch of blue's other friends. He had slaughtered each of them, one by one. Each death was even more gory and sadistic as the last.
Blue had frantically ran to his house, and there he saw it. Nightmare was covered in blood standing over blue's dusting brother.  "Papyrus?!" Blue sat beside their Dusting brother. "Papyrus please..papyrus..." Nightmare would put their hand on blue's shoulder. "He was in the way of our love, all of them were." Nightmare had said, a grin on their face as they pulled the sobbing blue close to them.