Hey, everyone.

So, this one-shot, originally called What Had To Be Done, was my prompt for day 2 of Gruvia Week 2018: Misunderstanding.

In the end, after a request from glodenglowingsnowdemon, I decided to turn it into a multi-chapter story. Now, let's make a few things clear before we go on with the story:

1- This will be a short story. 15 chapters AT MOST.

2-Updates won't be frequent, I'm afraid. Demons is still my priority and I have a few one-shots planned, so I can't promise weekly updates for this story. Since I've already written up till chapter 4, the first few chapters should be posted by the end of June, but after that I don't know. Hope you can understand that.

3-The pairings included here will be Gruvia, Jerza and whatever couples you might request. So let me know who you'd like me to include.

Original Summary: Gray didn't want to believe it. Didn't want to face the truth that was right in front of him, because it was too hard. He stared at her in disbelief, eyes drawn to the bloody knife on her shaky hands and for a moment he worried that she might use it on him. Was this his fault? Had he broken her so much that she decided to work for Zeref? (For Gruvia Week)

WARNING: This contains mentions of MURDER and SUICIDE. Therefore be cautious when reading.

Enjoy! Don't forget to review, follow and favorite.

"Do whatever you think is right! That's the way of the Fairy Tail Mages!"

-Makarov Dreyar

"You're working for Zeref." Gray didn't want to believe it. Didn't want to face the truth that was right in front of him, because it was hard. Harder than finding out that his parents had died on that awful night, or watching Ur sacrifice herself for him. No, this was so much worse.

He stared at the woman in front of him; her long blue hair was let down and she wore a beautiful gown. It used to be the color of the sky, but now there were red stains. Blood; he had noted.

Her shaky hands held onto the knife and for a moment he worried that she was going to use it on him.

"No." Juvia shook her head, tears streaming down her face and he was confused. Why was she the one crying? She had betrayed him. If anyone should be upset now, it's him.

"There's no use in denying it, Juvia. I'm not stupid." That wasn't entirely true. He had been stupid, and blind. His love for her had blinded him to the truth and now someone else had to pay for it. He really didn't know how he hadn't figured it out before, all the signs had been there.

The first one was a few days after they had gotten together, while they were training for the Grand Magic Games. She disappeared for a whole day and he had been worried sick. When she came back that night, she made up some excuse that the others were quick to believe, but not him. Gray always knew when she was lying, or at least he had thought so.

Then, on the second day of the Games, he heard Gajeel saying that he had seen her talking to a strange person, someone he didn't recognise. They had assumed it was perhaps a fan of hers, because Juvia had become quite popular ever since they returned from Tenrou Island.

She had made many pose ups for Sorcerer Weekly and after her relationship with Gray went public, the two of them became the it couple of Fiore. Only Sherry and Ren and topped them off.

On the night that Lucy was kidnapped after they found out about the Eclipse Gate, Juvia didn't seem as surprised as everyone else. Instead, her face showed sadness and guilt. Gray was suspicious, but once he asked her about it, she denied.

Later that night he had caught her talking to the same strange woman with long black hair and golden horns adorning her head. Natsu had been with him and he was able to overhear some of the conversation. All he was able to catch was the woman's threat to Juvie, before she suddenly disappeared. The words she spoke made him feel uneasy and he didn't like it one bit. "It must be done by midnight tomorrow, unless you wish for him to be harmed."

Gray knew that the woman was talking about him, but Juvia once again denied it when he asked. She told another lie; that the woman used to be a member of Phantom Lord and was trying to blackmail her in order to get money. Gray didn't know why he believed it, but he had trusted her. He loved her, after all, and he knew she loved him back, so there was no reason not to.

"I can't believe I trusted you." It was his turn to shake his head before he gazed at the body on the grass.

They were in the middle of the labyrinth consisting of the Palace Gardens and it was the night of the Grand Ball, as they had called it. A victory party to celebrate the defeat of the greatest threat to the kingdom of Fiore in centuries: the sudden reappearance of dragons about a week ago.

Most wizards were inside the palace; drinking, dancing and having fun. Gray had been having a great time with his friends, but then Gajeel told him he was worried about Juvia's disappearance, making the ice mage worried himself. They had agreed to meet at the party, yet over one hour had passed and she hadn't showed up.

So the two of them had teamed up to look for her and the dragon slayer had led them to their worst nightmare. They found her standing in front of the body, dress covered in blood and a knife in her hands. To say they were surprised was an understatement; they had never imagined she could be capable of murder.

Gajeel had stayed hidden, giving Gray the opportunity to confront her. He now wished he hadn't.

"I'm so sorry." Juvia was still crying as she let go of the knife. "I didn't... I didn't want it to end like this."

"Neither did I." He couldn't stay there anymore, couldn't look her in the eye. So he turned around with a sigh and began walking away.

"Wait." She called for him and he didn't stop. "At least let me explain." She sounded so sad, so broken. Not what you'd expect from someone who had just betrayed the person they loved.

"I don't think I want to hear it." Gray would never admit it, but he was afraid. He feared the reason she had chosen to change sides is because of him. Because of the way he had treated her before they got together, constantly ignoring her advances. What if he had broken her so much that she decided to work for Zeref?

"Still, you deserve an explanation." Juvia said and he froze. For a few moments, there was only silence as he considered his options. Should he hear her out? Or should he just walk away and save himself the heartache of knowing he was the reason she became evil?

He didn't have a chance to decide, for Gajeel chose that moment to come out of hiding. "You'd better have a very good explanation for this mess!" He glared at her and Juvia's eyes widened once she saw him. Sighing once again, Gray turned around and walked back to her.

"Why did you kill her?" He asked, glancing towards the body once again. Her hair was the same color as the blood that filled her dress and her big, brown eyes stared at them; a look of surprise forever etched on her face. Erza Scarlet was dead.

"I didn't want to." The water mage quickly said, her expression sorrowful. "But I didn't have a choice."

"Don't give me that crap! You're the one who loved reminding me that we always have a choice." Gajeel snapped and Gray wondered why he hadn't. He knew that he should be angry at her, but all he felt was sadness.

"Not in this case." Juvia replied before taking a deep breath. "I'm not working for Zeref." They stared at her, eyebrows raised.

"Seriously, you won't even admit it?" Now he was getting angry.

"I would never betray you like that." She firmly told them and Gajeel laughed without humour.

"Now that's rich." He shook his head while the ice mage remained frozen.

"You killed Erza. Don't you consider that a betrayal?" He reminded her.

"I was forced to do that after I found out..." She paused.

"What?" Gajeel asked, raising a brow while still looking furious.

"She was working for them." Their expressions didn't change.

"Do you seriously expect us to believe that?" Gray asked.

"I'm not saying she was a spy, but they were using her. Ever since the tower of Heaven, when they realized that she could be a great asset. So they placed a tracker inside of her; one that couldn't be removed even with magic. It allowed them to know everything they needed about Fairy Tail. They've been spying on us this whole time, just waiting for the perfect moment to make a move." She paused before looking back at Erza's immobile body.

"And that moment was tonight. They were going to destroy us by using Erza. They told me that they had developed the tracker so that it could be used to control her. I know Erza wouldn't have wanted that, so I did the only thing I could think of to stop them."

"You could have told us." Gray said after a few moments of silence. He was unsure whether or not to believe her, after all, she had lied to them about so much.

"Then they'd have killed you." Juvia replied calmly.

"Wait a second, why do you keep saying say 'them'? Weren't you talking about Zeref?" Gajeel quickly noted.

"They work for Zeref; they are his greatest allies." She took another deep breath before revealing a truth that could get them all killed. "Tartarus." Their eyes widened once they recognized the name of the dark guild.

"Tartarus?" Gray repeated, disbelief crossing his face.

"Yes. I managed to infiltrate their guild a few weeks ago." Their jaws dropped.

"Infiltrate?" Gray was having a hard time understanding what was going on. It seemed as if his brain decided to go on vacations.

"How?" Gajeel asked.

"It was Jellal's idea." She replied. "During the past seven years he found out that my mother had been a member of Tartarus until her death when I was five. Him and Ultear figured I might be able to infiltrate their guild and they were right. It took a while for them to trust me, but I managed to convince them that I had changed sides."

"So you've been pretending to work for them while trying to figure out their plan?" Juvia nodded. It was so unbelievable and yet, they believed her. Because they knew Juvia Lockser and the lengths she'd go to protect the people she loved.

"That's insane!" Gajeel stared at her in disbelief.

"You could've gotten yourself killed." Gray shook his head.

"It was a risk I was willing to take." A guilty look came upon her face. "I'm sorry I did this behind your back, but I didn't want to involve anyone else in this mess." He understood; if he was the one facing this situation, he'd have done the same.

"I understand." Gray paused. "But still, I don't think I can forgive you." She nodded sadly.

"I don't expect you to. I know that I'll never forgive myself for this, but it had to be done." She looked back at the body before kneeling down.

"You're an idiot." Gajeel said, frustrated. "You should have told us."

"If I did, they'd have killed you." She repeated. There was fear in her eyes and also sadness, regret. Gray had never been more sure in his life that she was telling the truth. But still, the question remained, could he forgive her after what she had done?

"Maybe. Or maybe we would've found a way to stop them and Erza wouldn't be dead." Erza had been like a sister to him, one of his best friends.

"I didn't want to risk it, all I wanted was to keep you safe." Juvia said before pausing as tears streamed down her face. "But I failed and now it's too late." Before either of them could understand what was happening, she had grabbed the knife from the floor and held it against her neck.

"No!" Gray screamed, taking a step towards her. He wouldn't let her do this. No matter how angry he was or how hard this was, he couldn't deny the fact that he still loved her. Even if she had been working for Tartarus, these feelings wouldn't go away so easily and Gray knew that there would be no pain worse than that of losing her.

"Don't do this." Gajeel pleaded. Juvia looked at them; so broken and so sad.

"I'm sorry. So sorry." She said while a shaky hand held the knife. "I don't want to do this, but it's too late for me now. They know I lied and they are coming after me."

"I won't let them hurt you, I promise." Gray took a few slow steps towards her. " I'll protect you." There was no way he'd let these monsters harm her. They were the ones responsible for this mess, he reminded himself. They had forced her to kill Erza, they gave her no alternative. They were the ones who needed to pay.

"That's the problem." Juvia sniffed, trying to stop the tears. "I can't let you get hurt because of me." He almost felt like laughing at the irony of the situation; wasn't it only a few days before when he was the one putting himself in danger to save her?

"Losing you will be worse than anything they could do to me." It was the truth. In that moment, Gray realized that even losing Erza couldn't compare to it. So he knew that, even though it might take time, he would forgive Juvia. He couldn't keep hating her for doing exactly what he would have done if he was in her place.

"But at least you'll be safe. They'll have no reason to hurt you if I'm not here." Juvia bit her lip as the knife inched closer to her neck, enough to draw blood. He started getting desperate.

"Please, Juvia." By then he was right in front of her and he knelt down. "Stay. Let me help you fight against them." Gajeel nodded, a furious look coming upon her face. He watched them silently, knowing that if someone could stop her from killing herself, it would be Gray.

"You can't. They're too dangerous; they'll get us killed." There was fear in her eyes, like he had never seen before.

"We won't let that happen." The ice mage took the hand that wasn't holding the knife and squeezed it. "We'll find a way to defeat them and Zeref. I promise you." He saw hesitation cross her face, but she didn't let go of the knife.

"I lost you once." Juvia gulped as memories of his death crossed her mind. "I can't go through that again."

"You won't have to, because I won't leave you again." He gazed into her eyes, letting her see the sincerity in his. "I love you, so please let go of the knife." He was filled with relief when her shaky hand finally let go of the weapon before falling to her lap. Gray wasted no time closing the space between them before taking her in his arms.

For a few minutes, he let her cry in his chest while he held onto her and whispered comforting words in her ear. They were so lost in each other that they didn't notice the moment Lucy, Natsu, Wendy and Levy joined them. They didn't hear the shocked gasps as the newcomers noticed the body on the ground or the thousand questions they directed at Gajeel, who didn't say anything.

Juvia pulled apart from the hug and attempted to dry her tears. "I'm sorry." She repeated as her eyes focused on him.

"It's okay." He whispered, a hand gently stroking her cheek.

"I love you too." A small smile graced his features before he leaned in. Her arms quickly wrapped around his neck and she brought him closer before they kissed. It was desperate and intense; she kissed him like it was the last time, tears still falling down her face.

"Seriously, what happened here?" Lucy asked after they pulled apart and the couple turned to her.

"It's a long story." Gray answered and Natsu raised a brow.

"We have time." He told them, crossing his arms.

"Okay." Juvia removed herself from Gray's arms and took a deep breath while she prepared to explain everything. He could tell she was nervous and scared, so he took her hand and squeezed it while giving her a reassuring look.

She was safe. No matter what happened, she was alright now and he vowed to keep it that way.

So, what did you think?

Did you like my portrayal of Gray and Juvia? Do you think he should've forgiven her for killing Erza?

Have a nice day, everyone!