Obsession ☭ Yandere Assassin x Reader

ʙᴏɴᴜs ⁴

So someone requested a side story that basically shows what would happen when Yoru found out that Izumi was obsessed with him and that he makes (Y/n)'s life harder. This happens after the stay epilogue btw! Enjoy ☆=(ゝω･)/

The sound of crying filled the house and normally, Izumi would ignore it, but today was different. Usually, after a while the crying would stop, but today the crying didn't stop. Izumi let out a sigh of annoyance and laid down the book he entertained himself with. He made his way to the nursery and opened the door.

As soon as the door opened, the sound of crying and screaming turned louder. Izumi quickly carried the infant in his arms and tried to comfort him. After a few minutes, the baby calmed down. Izumi set him down and quietly closed the door. As he walked, he clenched his fist in anger. When he reached yours and Yoru's bedroom, he slammed the door open.

You flinched as you woke up from your sleep. You had gotten a fever and Yoru left to buy some medicine.

"What the fuck, bitch? You were sleeping while my brother's son was crying?!?" Izumi shouted at you. With half lidded eyes, you stared at him in mixed confusion and fear. Before you could process what happened, Izumi grabbed your hair and dragged you to the floor. With a loud thud, you landed on the floor.

Your head ached as Izumi started shouting at you. He cursed you again and again until you weakly begged him to stop. "I don't see what he sees in you. The only good purpose you have is giving birth. Heck, you can't even properly take care of your son." Izumi spat. You looked up and was met with his foot colliding to your face. Before he could kick you again, Izumi was knocked down on the floor.

"WHAT THE FUCK DO YOU THINK YOU'RE DOING IZUMI?!" Yoru shouted as he held down Izumi. "Yoru..i-it's not what you thi-"

Before Izumi could finish his sentence, Yoru punched Izumi in the face. Meanwhile, you held your head in pain. It didn't help that you already felt tired before everything even started. When Yoru knocked out Izumi, he immediately went to you and carried you to the guest room. He got some ice and gently dabbed your face with it. Yoru felt angry as he saw that you were going through pain because of some worthless asshole. "I promise I'll get rid of him for you. You'll never have to go through that again, my princess."

- - -

Izumi woke up to a pounding headache and pain all over his body. He tried to move, but it was useless. It was as if his body was tied down by a bunch of restraints. He gathered all his strength to open his eyes and when he did, he was met with a blinding light. The door's opening widened and a person stepped in. Izumi squinted his eyes in order to make out the person's appearance, but was cut off as the person flipped the light switch open. Standing there, in all his glory was Yoru. The blond assassin closed the door behind him then walked towards Izumi.

"In my own basement, huh." Izumi's raspy voice uttered.

Yoru paid no mind to Izumi's voice. The room's floor was damp and the atmosphere was filled with a musty smell. The only light source was a small light bulb that hanged from the ceiling. The only furniture in the room was the chair that Izumi was tied to. When Yoru came into the light, Izumi noticed that he carried a tool box in his hand.

"You crossed the line Izumi." Yoru spat out. Izumi watched as Yoru set down the tool box on the floor and take something out. It was difficult to make it out, but with great difficulty, Izumi saw that it was a pair of pliers. Izumi went feral when he realized what was going to occur.

"Yoru..are you really going to do this to me."

Step.

"Yoru..!"

Another step.

"DAKU YORU!!"

Yoru stopped when heard his full name from Izumi's mouth. He gave him a smirk then slowly walked towards Izumi. The black haired boy knew that Yoru wasn't going to stop, so he trashed in his seat and tried to escape out of the various restraints that held him down. As Yoru went to pluck out a finger nail, Izumi whispered.

"I love you." Yoru halted his actions. Izumi noticed this and proceeded to open his mouth.

"Even when we were kids, I-I always treasured you like you were my own blood! I took care of you when you were sick or injured. I PROTECTED YOU FROM YOUR OWN FATHER AND THAT CAUSED ME MY DREAMS! EVEN AFTER, I STILL...loved you."

"I treasured all the things that you owned and touched. Your baby teeth, your underwear, toothbrushes, AND EVERYTHING THAT YOU USED!!! I DON'T UNDERSTAND WHY YOU WOULD ABANDON ME JUST FOR SOME GIR-"

Yoru snapped off a finger nail and Izumi's screams filled the room. This torture went on until all his fingers were mangled by using different tools. It wasn't long until Izumi was on the verge of passing out. "You're a disgusting piece of shit Izumi. You were never part of family in the first place. The only thing useful about you is your money."

Tears went down Izumi's cheeks as he heard Yoru's heartless words. The torture went on for weeks until Izumi's body couldn't handle it.

- - -

Yoru watched as the body burned into a crisp. 'What he did was disgusting and I always knew he was weird. Hahh, is this what (y/n) feels like when she saw my collection of her things? Nah, I doubt it. She loves me...no, she should love me.'

- - -

I was actually going to publish another chapter which I called, "True Ending," where (Y/n) commits suicide (cause her son looked exactly like Yoru and cause of depression). Yoru finds her body and kills himself as well, leaving their son to Izumi, who went crazy and swore to himself that he would never let your son fall in love, so he wouldn't end up like Yoru. But I decided enough was enough. Both endings are already sad, I didn't want to add more. I am not going to try and end this story with a happy ending because, well, I don't want to (＾ｖ＾)