Sempai - Zexion x Yandere!Reader

"Sempai" Zexion cringed at the word as he groaned in annoyance when you came running over to him. He never fully understood why you called him that, the word was foreign to him. He narrowed his only visible eye at you as you stopped in front of him with a wide smile on your face. Your [Eye Color] eyes staring lovingly at him as you admire his whole being.

"Yes [Your Name], what do you want?" The silver/blue haired teen asked, annoyance clear in his voice as he closed his locker door. He raised an eyebrow when you didn't answer, only standing there with your cheeks tinted pink and a love-struck look on your face. Growing impatient he turned on his heel and headed onto class, causing you to shake your head and run after him.

"Sempai, wait up" you called out, as the older teen only groaned and walked faster.

-Later-

"I just don't get why she calls me that!" Zexion exclaimed with a huff at lunch as he sat across Demyx, a gullible musician that always found a way to worm himself into peoples hearts. He looked up from his strange instrument and stared at his friend.

"Do you even know what that word means?" Demyx questioned, a cheeky smile on his face as Zexion shook his head.

"Do you?" The smaller teen asked his friend.

"Nope" Demyx said, soon laughing as his small friend snapped at him with an irritated look on his face. The two stopped once they heard footsteps approach their table as a long pink haired male soon stood before them.

"Hey Zexy" the male purred as Zexion groaned in irritation.

"What do you want Marluxia?" Zexion asked, he found the male to be even more irritating then you. The pink haired male laughed, sitting down beside the silver/blue haired teen and lean against him with a sly smile on his face as he watched the smaller male give him a glare that would put him six feet under. A couple of tables away your [Eye Color] eyes narrowed at the sight of the pink haired male being to close to your sempai. 'Zexion belongs to me' you thought with a sour expression on your face as a small growl ripped through your throat. Before a wide smirk spread across your lips as a brilliant idea crossed your mind, causing that small growl to turn into a fit of giggles.

-Time Skip-

At first Zexion didn't take much notice to the missing students. But soon he started to notice that it was only the students he interacted with, friends or occasional students who he would give a small greeting too, that were disappearing. He noticed a lack in your presence or how you would just stay quiet and stare at him with wide smiles and vacant eyes. He shivered, now uncomfortable with your presence more then irritated by it. Then came the day were he didn't see you at all, you were nowhere to be seen that day and it disturbed him.

As the bell for the end of the school day rang he walked outside of the school, not saying goodbye to Demyx or waving back when the taller teen gave a wave of goodbye before jogging off towards the football field where the band members were going to meet for practice. Left alone to his thoughts the small teen walked down the deserted and empty sidewalk. Shivering when he thought he heard the sound of footsteps following behind him. Stopping he started to turn around, only to find nothing behind him. Sighing in relief he started to face forward again only to be met with your wide [Eye Color] eyes staring into his own with a devilish smile on your lips. "[Your Name]-" he started to say before being struck in the head.

His vision started to fade as he crumbled to the ground, the last thing his saw before blacking out was your wide insane smile as you stared down at him.

-Later-

When Zexion came to, he groaned as his head throbbed painfully. He shivered at the feeling of fingers running through his hair as his head was rested on something soft. His wrist and ankles were bound together with rope as he looked around at his surroundings. The room he was in looked like a basement, as the stench of something rotting reached his nose. Looking around the room one more time, his throbbing head cleared as he stared in horror at the mutilated bodies and dried blood that stained the cemented walls and floor.

He tensed at the sound of humming as the fingers continued to rake through his silver/blue locks. Looking up with his icy blue eyes, they widen as he stared up at you. You had a wide smile on your lips, your eyes shining with insanity and infatuation as you hummed. His voice caught in his throat as you locked eyes with him, your smile widening even more then it was before. "Morning sempai" you said in a cheerful tone that didn't quite match the morbid sight that surrounded you and Zexion.

"Why?" Was all Zexion could choke out, fear evident in his voice as he froze when your fingers stopped midway in raking through his hair. Staring straight down at him you responded in a cheerful tone that sounded more darker then the one before, causing him to shiver.

"Because you're my sempai."