Natsu, being a dragon slayer, had extremely heightened senses. He could eavesdrop on conversations quite easily, whether he wanted to or not. This meant he overheard countless secrets from his guildmates over the years. And his sense smell - probably better than a bloodhound's! He could sniff someone out from a hundred yards away, which means he certainly smelled the arousal wafting from a certain blonde-haired mage, who was reading a book at her desk.
Lucy's scent was extremely calming to Natsu, but with the smell of her oh-so-obvious arousal mixed in, it became enticing. He knew that Lucy was special to him - he had known since the disrupted S-class trial took place. He just didn't see a reason to act on it. That, and he didn't know if she felt the same.
Of course, he smelt when she was excited around him, sometimes when they hugged and sometimes when she watched him fight. But that didn't prove emotional attraction. And yes, he had definitely overheard her talking to Levy, Cana, and many other girls about him, but she almost always denied the claims. It's not like Natsu could read people easily anyway - he didn't understand that Lucy would be embarrassed and lie about such claims.
"Hey, Lucy?" Natsu spoke, breaking the silence.
"Hmm?" She hummed, still entranced by her book.
"Whatcha readin'?" The dragon slayer asked.
"Mm," She thought about exactly what she was reading and who exactly was in her room while she read it. "Oh! Nothing!" She quickly spoke but tried to keep calm still. Her cheeks tinted red, realizing the predicament she was in. That swiftly broke the trance-like state she was in. She was reading a very good, and very sexual book that she had borrowed from her close friend, Levy.
And she was reading it while her best friend, and unbeknownst to him, her crush, was with her. And the part she was at was getting really heated. To be fair, she was reading it when he broke into her apartment. But, she still quickly shut the book and shoved it in her drawer.
"Really?" He spoke, a smirk on his face. "It seemed like you were pretty absorbed in that book... ever since I got here, actually. You've been ignoring me," His smirk turned into a pout, clearly messing with her.
Her face turned redder, but she tried to play it cool. She internally cursed her cheeks, why did they have to turn so red? He has no idea, she thought, taking a deep breath. "I don't know what you're talking about. It's just a normal, regular old book." She had looked up at him, for pretty much the first time since he got there, and noticed Happy was nowhere to be seen. "Hey, where's Happy?"
"The traitor? He's hanging out with Carla and Wendy. That's why I came over, 'cuz I'm soo~ bored." Natsu pouted again, Lucy just giggled.
A moment of silence passed as Lucy tidied up her already-spotless desk. Natsu watched her carefully, debating whether or not to tell her.
"Hey, Lucy?" He spoke, still a little unsure, but he smirked nonetheless. "You know I have a real good sense of smell, right?"
Still focusing on organizing her desk-top, she replied, "Mmhmm, because you're a dragon slayer, right? Why're you bringing that up?" She questioned him, still not understanding.
"Yup. I have good hearing, too, but my sense of smell can be more... informative." He emphasized the last word, and Lucy's eyes widened in realization, looking at him. Her face was scarlet red as she studied his face, trying to figure out if he meant what was implied.
"Wha-? What do you mean, Natsu?" She spoke quickly, frantically. Natsu thought it was kind of cute - how flustered she was. He chuckled, also finding it quite funny that she had never, not even once, thought about what his sensitive nose could pick up on.
She never really thought about Natsu's dragon senses outside of the situations it had been helpful, such as during a mission. She had no idea he could smell her... body, and know when she was feeling particularly excited. The thought of it made her uneasy, as she wracked her brain to think of the times she felt that way about Natsu. And not to mention, the things he might have overheard her say!
He grinned at her. "Calm down, it's not a big deal."
She pursed her lips, thinking about it, face still beet-red. He has never brought it up before, so he probably doesn't think about it often! She tried to reassure herself.
Natsu got up from where he was sitting on her bed and walked to her desk, where she was still sitting in her chair. "Lucy, I'm still bored." He spoke, pouting at her.
She got up from her desk, mustering all the confidence she could, and stood in front of him, looking him in the eye. She didn't care if he was bored, she wanted answers. "How come you never told me how good your sense of smell is?" Her eyes narrowed. "And what specifically you could pick up on?" she added, avoiding saying the words out loud.
"Not my fault you never thought about it." He replied, shrugging. Then he smirked and said in a deep, husky voice, "You have no idea the things I've heard and smelled. I know a lot more than you'd think I would."
Lucy, surprised by his sudden change in character, gasped lightly. The smell of arousal got stronger. "I- Natsu, I don't-" She didn't know what to say. She had never seen this side of Natsu before. After all their adventures together, she had only ever seen the fun, happy, carefree Natsu. Not to say she didn't like it - she clearly did, and she knew he knew she did. She took a few steps back towards the wall, but Natsu stepped forward every time she stepped backward.
The scent of Lucy, and her slight anxiousness, and intense arousal changed Natsu. Something came over him - he was still in control, of course, but he got bolder, more articulate, and he wanted Lucy.
"You know, Lucy," He spoke, stepping towards her, "You are so hard to figure out. Maybe I'm dumb, but you are one weirdo." He chuckled. "I can tell that you're so clearly physically attracted to me. God, it's painfully obvious." By now he had backed her up to the wall, and her face was quite red still, if not, more so.
He whispered, "But I can't seem to tell if it's emotional, too." He looked down, softly smiling, "You're so smart, always using big words, and you can read people so well, Lucy." He had that husky voice again. He stared into her big brown orbs, which made her shudder. "Me, on the other hand, well, I can't read people for shit." This was true. Natsu was an action man, he didn't use words well. He spoke through his touches, actions, movements. Not words. Oddly enough though, he wasn't doing too bad right then.
"Natsu..." She whispered, still at a loss for words.
He continued, "Lucy," He spoke deeply again. Every fiber of his being was telling him to kiss her, but he didn't want to ruin what friendship they had if she wasn't willing to take the next step. "Tell me," he got closer to her, faces inches apart. His eyes darted to her lips, licking his own, then stared back at her beautiful eyes. "How do you feel about me?" Her face, somehow, got even redder in reaction to his question.
She had always thought Natsu was this dense dummy, but his actions and words were proving her wrong. It shouldn't have been so surprising - he was a man, even if he acted like a child so often. He cared about her deeply, he was extremely overprotective of her. Why hadn't she seen this coming? He clearly implied that he was interested in her- no, infatuated with her.
She knew how she felt about him. She had slowly accepted it but fully realized when Natsu left her for an entire year. Her heart panged at the thought. It was good for them, she got to be on her own for a while, not using Natsu as her crutch as she often did before then.
She finally spoke, "Natsu, I..." she trailed off, licking her lips. For once, she wouldn't use the words she could normally so carefully sculpt together - right now, she didn't know how to. This time, she would use her actions, as Natsu so often did. Her eyes darted to his lips, lingering for a second, then looking back to his worried onyx eyes.
He patiently awaited her answer, which, again, surprised her. Her gaze went back and forth between his eyes and his lips as her small hand lifted up to rest on his cheek, her thumb gently stroking it. She ever so slightly moved her face closer to his, tilted her head, and slowly closed her eyes as her lips pressed on his.
He quickly responded to her kiss, smiling into it, moving one hand to grab the back of her head and bring her closer, deepening the kiss, the other wrapping around her waist. Lucy moaned ever so lightly at his touches, not used to them in a sensual way.
She deepened the kiss, even more, herself this time, and moved her hands into his hair, grabbing at the surprisingly soft spikes.
She reluctantly, slowly pulled away and gave a small smile. "Natsu..." She looked into his eyes. "I do love you."