Sorry for my english but I want to post this in ASAP.
Ace and (y/n) were bestfriend since their childhood. (Y/n) is a bit boyish and Ace is a handsome man who can melt a lot of girls' heart. Usually they're like to play basketball at certain place and marked it like they owned it. That place is at surrounded with nature and and there is a huge tree with tree house on top of it.
Ace tried to climb on tree to get on the tree house but he fell while (y/n) have no problem with it. As (y/n) get inside treehouse, she used her pocket knife to carve something on the tree that is center of the treehouse. However, Ace was standing on the ground level, staring on top, wondering what is his bestfriend doing. (Y/n) wrote her name and Ace in heartshape on the tree with her pocket knife and she knew that her bestfriend wouldn't see this as he can't even climb on top.(Just a quick sketch)
Currently, in their adult age, (y/n) is still the same, tomboy. And they're still together as bestfriend and play basketball as their hobby. On one day, Ace met a woman named Vivi and he had himself fallen in love. Ace introduced her to (y/n). But he didn't know that (y/n) fall in love with him since childhood. Of course, she felt sense of jealous.
One day, he planned to confess to Vivi and he love her. (Y/n) tried to dress as a proper lady. By the time Ace saw (y/n) he told her that he want to confess to Vivi that he love her. (Y/n) felt really heartbroken till she run to the forest and got herself badly injured by fell down from the cliff.
Meanwhile, Ace has already confessed to Vivi and he fallen in love her. And they love each other and kiss. When they pulled out, he saw a blood from Vivi's lips and she had to go hospital.
Ace sent her to seek treatment for her heart disease. At the same time, he saw his bestfriend were sent to emergency, whining. (Y/n) feel severely pain on his leg majority as the branches went through both of her legs.
For Vivi's case, there's no one willing to donate a heart for her and (y/n) is forced to have her legs amputated.
(Y/n) laid on the hospital bed, emotionless. Ace come over to her ward and saw that the nurse is trying to give her food but she ignored. So Ace took over the nurse and asked her to eat. But she doesn't want to.
(Y/n) felt upset as he hurt her feeling that made she lost her legs. When Ace told her about Vivi, (y/n) could see that Ace feel sad about that news as he might lose Vivi.
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Few days later,
Ace receive a good news that Vivi found a donor. Ace felt relieved and happy that he could spend his time with her. It was more than good news for him. So he picked her up and sent her to her home and cooked some food.
It was raining on the next day. He receive a call from (y/n)'s brother.
Then, his whole body freeze like statue. He doesn't believe at first but they told him the truth.His bestfriend passed away.
When he arrived at the cemetery, (y/n)'s brother gave Ace a final letter from his best friend. When (y/n)'s brother is gone, Ace slowly opened the envelope and read it.
Dear Ace,
If you read this, it means that I'm no longer in this world. We're no longer seeing each other again, playing basketball together. But to be honest, you're really hurt me so badly. We've known each other since we're young and yet you love Vivi that you met a month ago. My heart is really hurt when I saw you and her together till I went to crazy. But when I seeing you feeling sad because you might lose her, I feel that I shouldn't be happy. Then I decided to sacrifice myself and donate my heart to her, so she could live with you. I'm not doing this for her but my bestfriend and the man I love. I love you, Ace. But this is good bye.~ your BFF
(Y/N) ♡Ace doesn't know what to think. How could he doesn't notice her feeling ?
He sat beside her grave and cried on it.After that, he rushed to the treehouse and yelled her name from below.
"(Y/n)!! (Y/n)!! I know you're inside, (y/n)! Come out!"
He received no respond. He have no choice but to climb the tree to get on the treehouse. But this time, he won't fall. The weather started to rain heavilly once Ace got himself inside the treehouse. He scanned around the treehouse and he stopped at the certaib spot of the tree. He saw his name and his bestfriend's name in heartshape.
"Why?! Why did I fallen in love with Vivi but not you?! Why I didn't notice your feeling?! I'm sorry..."
He started to cry and yell.
"I'm sorry, (y/n)! Please come back! Come back, (y/n)!" He begged.
Once she left, she will never coming back...
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I know that my english is really terrible and I didn't explained this one shot in detail. I hope you're understand what I'm trying to say.
Please comment~~~ I might reply
And also give a suggestion. By the way, this story is actually from one of the indonesia film called 'Heart'.