You are the Reason (Johnny x reader)

Prologue

In the beautiful city of Calatonia, humanoid animals, great and small, were living wonderful lives. Some went to school, some went to work. Some spend their day at a restaurant, some spent it at the park.

At the park, a 26-year-old koala named Buster Moon and his dad went on their usual Sunday walk. They were just about to go back to their house when they heard something crash in an alley. Curious, they looked in the alley and gasped. A little human girl with (h/l) (h/c) hair laid unconscious with blood on her forehead.

"Oh my god!", Buster exclaimed rushing to her, his dad followed.
They tried to wake her up but she still had her eyes closed.
"I'm calling the ambulance.", Buster's dad said taking out his phone.

A few minutes later, the ambulance arrived and laid the little girl on the stretcher.
"Do you know what happend to her?", the doctor asked Buster and his dad.
"We don't know what happend. We just heard something crash in that alley, looked inside and found her unconscious.", Buster's dad said.
Buster nodded in agreement.
"Would you like to come with us maybe she will just talk with someone who she trust since you two are the ones who found her."
The two nodded getting in the ambulance.

Time Skip

The little girl laid still unconscious on a hospital bed, a bandage around her head. Buster and his dad sat at either side of the bed waiting for her to wake up.
"How long do you think will she be unconscious, Dad?", Buster asked.
"The doctor said that she will wake up soon."
"I hope so."

Buster laid his hand on the little girl's one. From the feeling, the eyes from the little girl slowly fluttered open. Confused, she looked around the room till her eyes locked with Buster's.
"Finally you're awake!", Buster said relieved.
"Who are you? What happend?", she asked holding her head.
"I'm Buster Moon. My dad and I found you knocked out in an alley. What's your name?"
"My name is (Y/N)."
"How old are you, (Y/N)?"
"I'm (your age minus 15 years)."
"Do you know where you come?"
(Y/N) tried to think but she had nothing so she shook her head.
"Ok, do you know your parents name maybe we can contact them."
"I can't remember anything. I just remember my name and birthday."
"The doctor already feared it.", Buster's dad said.
"What do you mean, Dad?"
"The doctor said that she hit her head pretty bad and that she could have a memory loss. Well, it looks like it's true."

Suddenly a knock came from the door, it opened revealing two rhinos in police uniform.
"Good afternoon, the doctor of the hospital called us about what happend in the alley this morning. We have some questions."
Buster and his dad answered every question about what happend when they found (Y/N).
"Ok, now we have some questions for you, little one.", one of them said referring to (Y/N).
(Y/N) nodded. She could just tell her name and her age but not where she comes from.
"Ok, since you don't know where you come from, we have to take you to the youth welfare office so they can take of you."
Scared, (Y/N) shook her head and hide herself under the blanket.
"Can't we make an exception?", Buster's dad asked.
"What are you proposing, sir?", the other police officer asked.
"I have the feeling that since she lost her memory that she's having issues to trust someone. The only people she has talked to is my son and she seems to trust him. I say we take her with us and she stays with us as long as she hasn't regain her memory."
"Very well, we let her stay with you for a year. By that time, if she hasn't regain her memory or there isn't someone who is related to her ..."
"Then we will adopt her.", Buster suddenly said.

Hearing those words, (Y/N) came out from under the blanket and looked at Buster in shock.
"What do you say, (Y/N)? Would you like to live with us?", Buster asked.
(Y/N) nodded smiling at him.

A year later

During the year, Buster and his dad tried everything to make (Y/N) remember where she comes but nothing helped. Every Sunday, they went to the same alley to help her but she remembers nothing. Now, the three were at the adoption house.

"Well, since (Y/N) can't remember anything from before the accident and that no one is related to her, I need to ask you, (Y/N), do you accept this adoption?", the director asked.
"Yes.", (Y/N) accepted.
"Well, then I need your signature, Mr. Moon."
Buster's dad signed the paper.
"With my signature, I hereby declare that (Y/N) is adopted by Mr. Moon. Congratulations."
"Welcome to the family, (Y/N) Moon.", Buster and his dad hugged (Y/N), happy to have her in their family.