Yandere!Under verse x Reader

The Mind Siblings

A/n: about 4 years have passed since last chapter and now. Y/n 511, but 21 physically. Dream is 14 physically, but 512 in actuality.

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Over the course of 4 years, Error hasn't visited, mostly because Y/n has scared him....but they still do text. Ink comes over the most, and Nightmare hasn't visited at all, seemingly unable to come over due to the positive aura that now surrounds the au. Y/n has been teaching Dream how to fight and use his powers, and he has quickly learned. Y/n has taken Dream to Memorytale various times so he has friends, and so the others can help him with his powers. At the current moment, Y/n is just relaxing outside while Dream and Ink are traveling au's, with Ink teaching Dream how to teleport from au to au, and make portals. Feeling the air get colder, Y/n already knows who has arrived.

Y/n: Hey, Nightmare. How are you?

Nightmare, narrowing his eye: You know something.

Y/n, humming softly: I do. I'm not going to deny that.

Nightmare: is that why I haven't been able to come here? It's been too positive...

Y/n, opening their eyes: huh..you can't travel through positivity? Only negativity? I mean, it makes sense, but still-

Nightmare, sighing in annoyance: Yes..who else has been here?

Y/n: wouldn't you like to know weather boy.

Nightmare, confused: what?-

Y/n, waving him off: just an internet reference. Don't worry about it, 'kay?

Nightmare, grumbling: fine...but who els-

Dream:...Nightmare?

Y/n quickly sits up, their expression now 'oh shit' as Dream looks shocked to see Nightmare, and NIghtmare just as shocked...before getting angry and looking at Y/n.

Nightmare, tentacles lashing: HE'S BEEN ALIVE THIS ENTIRE TIME?!

Y/n:...yes?

Nightmare growls in annoyance, his fists clenched. Dream gets his bow out and shoots in-between Y/n and NIghtmare. Nightmare looks shocked, and Y/n doesn't even looked phased, used to this. Nightmare turns to Dream with a scowl, wanting to attack. Y/n quickly gets up and goes in-between both of them, stopping any attacks that may happen.

Nightmare: Get out of my way and let me kill the ball of positivity!

Dream tenses, his bow still out and is now pointed at Nightmare. Y/n looks annoyed, questioning their own life.

Y/n: Look, if both of you are going to be here...then you can't attack each other, no matter the grievances you have with each other!

Nightmare: but-

Y/n: No buts Nightmare!

Dream snickers and Y/n gives him a semi-annoyed look, before looking back at Nightmare, who also seems annoyed, his tentacles lashing.

Y/n: As long as both of you are here with me in my home, you aren't allowed to fight each other. I refuse to pick a side with you two. I'm not going to spread despair, or joy....I will simply be neutral, helping those I can, and harming those that must be harmed. I am neutral and I will be that way.

Nightmare, rolling his eye: oh come on. You can't be neutral forever, you'll give in eventually.

Y/n:...you wish I would! I'm not going to chose a side. If you want my help, then you ask for it. It depends on what you ask for in order to make me help you...but never ask me to kill someone, 'kay?