Lucy was getting worse; Natsu noticed as he stared down at his partner. Her skin was so pale, she looked ghostly. The sudden rain hadn't helped either. It had drenched both of them in the time it took to locate a decent shelter. They were huddled together in a hollow of a tree. Luckily it was large enough that both of them could fit inside, though it left little space to stretch out. He couldn't start a fire to dry their clothes or warm them, in case he accidentally burned down their only shelter. Lucy was unconscious, but he had to dry and warm her somehow.
Natsu placed his back to the farthest part of the tree, and cradled Lucy to his chest. He was trying to make sure every part of her was touching him, so she could get dried quickly. He raised the heat of the air around them, insulating them in a cocoon of warmth. Their clothes dried rapidly, the water evaporating away.
Despite his efforts, Lucy was still shivering constantly, even though she was hot to touch. Her chest rose and fell rapidly as if she was having trouble breathing. His brow knitted together in worry and anger as he watched over Lucy. "This is all my fault, Lucy." He whispered angrily, his fists tightening as he held her closer.
They had been trekking through the forest on their way home from a somewhat successful mission. Most of their reward money had gone towards the damages he had caused, putting both of them in slightly sour moods. Natsu wanted to get back to the guild quickly, so they could start another mission to make up for the loss of finances. Lucy had suggested taking the train back to Magnolia, so they could rest up on their way back to the guild. Both of them had used a lot of magical power in order to subdue a monster that had been terrorizing the town. They weren't at 100% yet and travelling by train would help to build their energy back up. However, Natsu turned slightly green at the thought of sitting through the torture known as transportation. Happy had laughed at him, teasing him for his fear. He brushed off Happy's comment, suggesting they go through the forest instead. He claimed it was a short cut back to the guild.

"Plus, fresh air would build our magic back up faster than some stuffy air on a stupid train." He argued. Lucy looked off at the forest and smiled weakly as she agreed to walk home. Natsu had internally cheered and applauded himself for escaping the evil clutches of the train.
Once they were packed, the trio headed back to Fairy Tail through the forest. Natsu had kept up a fast pace. He knew the forest could actually turn out to be a faster way home, if they kept up that gait. He was charging right along, thinking about fighting Grey, challenging Erza, and taking on their next mission when he heard Happy frantically call out his name. He turned around and stopped. Happy was hovering above Lucy, her collapsed figure face down on the forest floor. He ran back to them, quickly turning Lucy over and noticed her labored breathing. Happy landed next to her, placing a blue paw on her forehead.
"She's really hot. I think she has a fever!" His voice sounded higher; his worry raising it. "She was saying she was a little tired, and I told her we could rest. But she just smiled and said she could keep going. I should have stopped her. I-"
"Happy, fly ahead and get help."
"Natsu?"
"There's no time. Lucy needs help and fast. It would be too dangerous to fly with her, so you need to bring help here. You're fast and I know you can do it. I'll stay and watch over her until you get back." Natsu directed his friend, trying to mask his own worry. Lucy's condition looked serious and there was no time to waste.
"Right." Happy said, his worry turning to determination. "Natsu protect Lucy until I get back." He released his wings and ascended into the air. "I'll bring help, don't you worry!" He shouted as he shot above the tree tops and out of sight. It wasn't long after that that the rain came, bringing them to their current situation. If only he had noticed. If only they had taken the train. If only he hadn't been such a coward. His anger at himself was growing. How could he had been so stupid, so reckless? Lucy was like this because of him. She was pushing herself harder than she needed to, because he was only thinking about himself. "Stupid. Stupid. Stupid. STUPID!" He cursed himself under his breath, reflecting on his selfishness. They were a team, but he didn't think of her at all. Lucy coughed, making her already shivering body rattle harder. Tears pricked Natsu's eyes as he watched her suffer. He felt so useless. All he knew was destruction. When his partner needed him the most, he couldn't do anything to help her.
"I'm sorry. I'm sorry. I'm so sorry." He muttered against her hair as the rain fell harder.
"Natsuuuuu!" Happy's voice called out to him, before the blue cat appeared, wet from the rain. In his paws Natsu noticed a small vial with purple liquid inside.
"Happy!" He was so happy to see his friend, cutting away some of the worry he was feeling.
"Natsu, there's no time." He said as he walked towards him. He handed the vial over to Natsu.
"Is this?" He questioned.
"Yes, it's the medicine that can help Lucy. You have to give it to her now to stop the progression of her fever. She has to drink all of it or else-" Happy stopped himself from voicing what they both dreaded. The small Exceed shook his head, clearing his mind of such a taboo thought. "I have to go back now. I'm leading a doctor here so he can help Lucy. He sent me here with this so she wouldn't get worse." Happy spread his wings and stared back at Lucy, worry and fear in his eyes. Natsu tightened his grip on the vial.
"Thanks buddy," Natsu said, smiling weakly at his friend. "Go, I'll make sure she takes it."
With a nod, Happy flew back into the rain to lead the doctor to them. Natsu shifted his hold on Lucy, propping her up enough so she could drink the medicine. He uncorked it with his teeth, gently pressing the vial to her lips.
"Come on Luce." He said, shaking her gently to wake her up. He pressed the vial towards her lips again, but she still didn't move. Her breathing was getting shallower. She felt so weak in his arms.

"Damn it!" He shouted out in frustration. He looked down at the vial, the purple liquid sloshing inside. This would save Lucy. This would stop her suffering. Happy had said it would buy her time. Natsu stared down at his partner, knowing he didn't want to imagine what it would be like if she wasn't there.
"Lucy," He whispered. "You heard Happy. You have to take your medicine." He tipped the vial back against his lips, tugged gently on her chin to part her lips, and pressed his own against them. The medicine transferred quickly to her, but Natsu held her closer to him, making sure she received every single drop. He couldn't lose her. Not now. Not ever. She was precious to him, and Natsu was willing to do anything to make sure she stayed by his side. Fairy Tail wouldn't be the same without her. Lucy was Lucy after all.
He broke away from her, staring intently at her face. How long would it take for the medicine to work? Did she drink all of it? Was he too late? These thoughts raced through his mind as he willed the medicine to work. The tears that had been pricking his eyes were gathering dangerously together. He shut his eyes tight, not being able to stand the sight of her in so much pain. Pain that he had caused.
"I won't complain about transportation ever again. I'll ride every train in Fiore. I'll do it. I promise. You just have to promise you won't leave me." Natsu cried, holding her tighter. She couldn't leave him if held on to her like this, right?
"Lucy" He sobbed.
"Na-Natsu." A weak voice spoke up towards him. Natsu gasped as he looked down at her. Her complexion was still pale, but several shades healthier than they had been moment ago. She didn't feel as warm as she had before, and her body was no longer shivering. Lucy was staring up at him, her brown eyes shining.
"You're so warm" She commented, closing her eyes and smiling, while snuggling closer to him.
Just like that, the tension and dread that had been building up inside of him disappeared. The medicine worked! His shoulders sagged; his muscles relaxing. He wiped his tears on the back of his arm, smiling down at Lucy, feeling lighter than rain had stopped, and the moon light slowly drifted inside, illuminating the hollow.
"You get me so fired up." He responded, before leaning his head against the back of the tree, closing his eyes, feeling as if he had just won a battle.

The next morning, Lucy awoke alone in a hollow of a tree. She felt a little weak, but otherwise normal. She sat up, blinking against the sunlight that was streaming down on her.
"You're awake!" Happy came running in, jumping in her arms.
"Happy," she greeted the Exceed, stroking his soft blue fur. "Where's Natsu?"
"He's helping the doctor load his supplies back on the carriage."

"Doctor?" She asked, confused.
"Lucy you were really sick. Don't you remember?" The Exceed looked up at her, worry in his eyes as he remembered the state she had been in.
Lucy blinked, trying to remember. She had felt faint and hot. She remembered closing her eyes for a moment and then woke up here. Everything else was really hazy.
"I'm sorry Happy, I can't remember anything." She said, shaking her head slightly.
"That's alright," he beamed up at her. "The doctor said you're all better now. All you need to do is rest. We'll take the carriage back to the doctor's village, and there's a train that will take us back to Magnolia. By the time we get back home, you should be as good as new!" He spread his paws high in the air, signifying his delight at that thought. She smiled down at him again, appreciating his concern.
"Thank you for taking care of me Happy. I owe you a fish when we get back to the guild." She giggled as his eyes went wide with delight.
"If that's the case, you'll owe Natsu some fire chicken too. He stayed with you all night while I got the doctor and even made sure you took your medicine." The Exceed skipped out of the hollow indicating he'll tell the doctor that she was awake now.
"Natsu?" Lucy tried to remember anything from last night, but her fever had jumbled up her memories. Flashes of images came to her she couldn't understand. A voice calling to her. A softness against her lips. The sound of crying. A warmth she couldn't get enough of.
"Lucy!" Natsu's voice echoed in the space. She gasped as he appeared, stopping her from remembering further.
"N-Natsu!" She called back startled by him. Her face grew suddenly hot, and her heart skipped. Why was that? She wondered. And why the hell am I blushing?
"Lucy your face is all red." His eyes widened in alarm as he came closer to her. "Has your fever come back?" He placed his forehead against hers, checking her temperature.
"Y-You...You're too close!" She yelled, pushing him away. He stumbled back, falling out of the hollow.
Happy flew in and started laughing. "You're causing trouble again. Aren't you Natsu?"
"I was just making sure she was alright." He protested.
"I'm fine!" She shouted back, confused as to why she was so flustered.
"Come on. The doctor is waiting to take us back." Happy said, ushering them towards the carriage.
"Transportation." Natsu groaned turning slightly green. A flash of memory of Lucy sick and shivering stopped him from complaining further. He jumped to his feet and shook his head and smiled.
"Alright let's go!" He held out his hand to Lucy, smiling just for her. "Come on Lucy!"
She stared up at him as she took his hand.

"Yeah. Let's go home."