𝐀𝐋𝐎𝐍𝐄 𝐅𝐎𝐑𝐄𝐕𝐄𝐑 ━ 𝑑𝑒𝑚𝑜𝑛 𝑠𝑙𝑎𝑦𝑒𝑟 𝑜𝑛𝑒𝑠ℎ𝑜𝑡𝑠 [✓]

✦ | His Only Obsession

muzan x fem!reader
tw : yandere behavior
lowercase intended!

A WEAK HUMAN CREATURE with the name of l/n y/n managed to capture the heart of the demon king. his love was so strong that it grew to something much darker and deeper than it was supposed to be, an obsession. 

he was clearly obsessed with her, his obsession was something beyond this world, and it was getting out of hand. y/n was humming a tune as she cooked dinner for herself, she knew that muzan was the king of all demons, yet, she accepted him for who he is with a kind heart. "what are you doing out of your room?" a voice asked curiously as y/n turned to face muzan. "hello dear, i'm just cooking, i got hungry," y/n said as she made a bowl of ramen for herself. 

"you should've asked me to get you something on the way home," muzan said silently as y/n slurped on her ramen and chewed happily, the sight made muzan's cold demeanour melt. "homemade ramen is better," she manage to make out while eating. "don't talk while you eat dear," he said softly as y/n nodded happily. 

"after this, go back to your room, alright? don't make me lock you up again," muzan warned as y/n gulped nervously and her eyes were wide at the memory when muzan locked her up in her room since she was nearly kidnapped by the demon slayers since she was a human and they thought she was being held hostage, y/n shuddered at the memory as she ate the ramen quickly. 

ever since that day, after killing the demon slayers rather savagely, muzan had been locking up y/n in her room ever since, it wasn't only for her safety, but it was to reassure himself that she would only be with him and him only, nobody else. no one in this world will be with her unless it's him. 

veins popped into view as his teeth gritted at the thought of someone else other than him being with her. he quickly grabbed the girl's arms as he dragged her towards his room, the anger in his heart burned brightly as y/n held a confused expression. "muzan? are you alright?" y/n blinked at him but muzan's grip only tightened before he threw y/n inside the room with barely any strength, but it was enough to send her laying on the floor, she winced. 

"muzan, what the hell?" she groaned in pain as muzan stood over her, his face swelled up in anger as she gulped. "you're mine, do you know that?" muzan asked. "of course i do," she said softly. "having the thought of you being in someone's else's arms angers me," he said as he clenched his fist. "so this time, i'm really making sure you're never going to meet someone, unless it's me." 

with that, he shut the wooden door and locked it with a lock. y/n's eyes widened as she stood up painfully and banged her fist repeatedly at the door. "muzan! you can't do this!" she said as she kicked the door but it was locked. y/n sighed in defeat as she leaned on the door and started falling down before plopping on the ground, sitting.

millions of thoughts flooded into her head as she just noticed at that moment that he wasn't in love with her. he was obsessed. y/n couldn't help but felt her heart plummet down to her stomach and she felt sick. her patience with him snapped that instance. 

y/n then noticed the window, it was open. y/n quickly rushed towards the window as she desperately climbed out. she slid down the roof and landed cooly on the ground before running away, reaching to grasp freedom. she felt a hand gripped on to hers as she turned around to face an absolutely furious muzan. "do you really think that you could escape?" he asked. "let me go, muzan! you're such a delusional person, i have had enough of you!" she said as those words cut deeper than yoriichi's blade. 

one look at muzan's face, she stopped. she knew that she was powerless against him and he looked even more furious. "my y/n," he suddenly said before he played with her fingers, but then one of her fingers snapped as y/n screamed in shock and pain. "stop saying such lies," he said. "you know that you love me." 

"tell me you love me."

"why can't you say you love me?" 

he asked angrily as he gripped on to her wrist, his grip was immensely powerful, making her wrist shatter as y/n screamed again as she tried pulling her hand out of his grip. tears escaped from her eyes as she felt pain, coursing through her body. muzan couldn't stand the scene as his heart softened. "just say it, and i wouldn't need to snap your neck," muzan simply said. "f-fine, i l-love you," she whispered out as she kept on sobbing, the pain coursed through her whole body. 

"good. just so you know, you're my only obsession."