Pulling My Heartstrings (Undertale Au Smut)

Nightmare x Reader

My heart pounded in my chest as I came to a stop, I had been running and hiding for what felt like hours... I heard a dark chuckle behind me, causing me to freeze and whip around as I saw my childhood best friend Nightmare. I teared up as I backed away in fear, he was different... he was taller, had these tendrils that extended from his body, and his bones were covered in some sort of tar like substance, not to mention his mood was so much more scary... it was like a switch flipped on him.

"You can't run forever." He said with a sickly sweet tone , a grin on his face.

I felt my back hit a tree, I gasped and looked away in a panic ...

"No matter where you go, I'll never leave you~" He purred, stepping closer.

I looked back at him, my breathing shaking.

"So let's just accept it~"

"N-Nightmare please! What happened to the friend I knew?"

He chuckled and grabbed my chin, his hold being gentle despite the grip he had, his other hand gripping my waist and pulled me against him.

"Right here~" He purred, a light blush on his cheeks.

"N-Nightmare I-"

"Sshhh~" He interrupted, leaning in close to my ear.

"Don't tell me you never felt this way."

"Wh-what?" I asked, blushing brightly.

"Don't play dumb." He replied, nuzzling into the crook of my neck.

"N-Nightmare-"

"Just admit you want me as more than a friend."

I was about to protest when a sharp pain went through my shoulder, I yelped and gripped his hoodie.

"Admit it." He repeated.

"W-Wha - aahh! ~ "

He bit down harder, pulling an odd noise from me. I felt him smirk against my skin,

"Was that a moan I just heard~? You little masochist.." He purred, trailing the tip of his tongue over the bite.

My face heated up, I was trying to think straight but my mind was becoming fuzzy.

"Come on, tell me~" He cooed, looking into my eyes.

"I... I..."

He raised a brow, grinning and licking his lips.

"Yes~?"

"I... I-I've always liked you , but you arent acting like yourself- "

Nightmare smirked, his grip tightening as he pinned me to the tree.

" I t hought so~ and no need to worry about me.. I'm perfectly fine now that I have you right where I want you "

He then proceeded to attack my neck with bites and kisses, making me shiver and whimper. He chuckled, grinding against me and making me gasp and moan.

"N-nightmare..."

"You know, that's such a pretty sou nd~" He smirked darkly.

I was about to reply when he pressed his teeth against my lips, I melted and closed my eyes, kissing back.

"Mmmm~"

He purred, deepening the kiss. My body was heating up and I could feel something wet between my legs. He broke the kiss, pulling back with a string of saliva connecting us, a smirk on his face as he saw how flustered I was.

"You have no idea how long I've waited for this moment."

He leaned back down, his tongue sliding across my neck, making me shiver.