Disclaimer: I do not own Fairy Tail, or any of its associated characters and lore. That right belongs to Hiro Mashima.
Head Over a Mermaid's Heels
Hargeon Town, Kingdom of Fiore, Ishgar, Earth Land, July 2, X784
After being separated from his Dragon adopted father, Igneel, as a kid, Natsu Dragneel wondered Fiore for a time before he collapsed from exhaustion and was helped to recover by the Master of the female-exclusive Legal Wizard Guild, Mermaid Heel. Although the Master did make a persuasive argument that Natsu could do well in another Guild that accepted both women and men, the latter had gotten so attached to Mermaid Heel's members, especially a girl around his own age named Kagura Mikazuchi, that he didn't have the heart in him to leave which led to his behind the scenes position as an employee of the Guild rather than an actual member and it had been like that for almost seven years.
As a Guild employee, Natsu's job usually consisted of grocery shopping, holding luggage for arriving and departing members, and stocking shelves at the Guild's base/restaurant where he also cleaned and cooked at, so long as no patron saw that there was a male worker at a Guild renowned for its unique image as a women's only Guild. While Natsu's employee status kept him from going on any Guild Jobs on his own, he nonetheless trained his Magic and supported Kagura as well as the other members of Mermaid Heel such as Risley Law, Araña Webb, and a nine year old girl named Beth Vanderwood in the following years which occasionally led to some adventures on his part, especially when he and his friends found a mysterious egg the year after he first came across the Guild which hatched a blue-furred cat creature that he named Happy.
Although the whole occupation had its boring moments, Natsu nonetheless braved through with the dream to convince the Master to make Mermaid Heel open for men with him as the first male member which was his biggest priority next to finding Igneel. It was the latter goal in fact which brought Natsu to Hargeon with Happy, Kagura, Risley, Beth, and Araña accompanying him.
"Don't you think that the idea of finding a Dragon in a well-populated town is a bit too optimistic, Natsu, even for you?" Araña couldn't help but point out as soon as Natsu recovered from his train-induced motion sickness and their group of six began to explore Hargeon. While she, Risley, and Kagura didn't want to discourage the Fire Dragon Slayer, they couldn't help but view the situation with a realist perspective.
Natsu waved off the question. "It's alright, Araña. I know that I shouldn't be expecting Igneel in town, so I'm just looking for this Salamander guy in question."
Kagura hmphed in condemnation as if she was disappointed earlier at something. "You probably would still be expecting him if I didn't point out to you and Happy that an oversized, red colored reptile with wings that can breathe fire would stand out in the whole area and make the entire country aware of what was happening."
"Aye, that is true." Happy commented with his usual smile in spite of the sweat on his face and the look of Natsu's wounded pride on his own.
After taking a moment to laugh at the boys' short-sightedness with Risley and Araña as Kagura merely smiled, Beth asked Natsu. "So, if you know that Salamander isn't a Dragon, why do you want to meet him?"
Taking the chance to explain and get his pride back in order, Natsu said. "Because I'm all but certain that this guy's a Dragon Slayer. Otherwise, he wouldn't be named after a fire breather. Even if he's a Second Generation, he probably knows something about Dragons. It's definitely worth a look if nothing else."
"That's actually pretty smart, Natsu." Risley complimented before smartly adding. "Probably owe that to Kagura's methods, though, but it's the thought that counts."
Natsu couldn't restrain a pout at Risley's words as she, Happy, Beth, and Araña laughed at his expression with even Kagura looking at it all in amusement before they then all heard girlish shrieking nearby which led them to a crowd of women fawning over a smug-looking man with blue hair that they all referred to as the famous Independent Wizard, Salamander. Looking at the overrated display, Natsu couldn't help but groan as he and Happy traded unimpressed looks while Araña, Risley, and Kagura narrowed their eyes in a curious way.
Beth, on the other hand, appeared lovestruck as she said. "Wow, he's so handsome!"
"What?!" Her group let out in surprise.
"Beth, what has gotten into you?!" Kagura snapped before slapping the back of the girl's head which made enough of a noise that surprised a nearby blonde girl that was looking at Salamander with similar affection just until then.
"Ow!" Beth yelped before she then began to blink her eyes repeatedly before looking back at Salamander being praised. "What's that stuck up looking happy about?"
"Huh?" Natsu and company looked at Beth in confusion before Happy walked up to her and pulled at her pants.
"Beth, don't you remember calling him handsome?"
"What?" Beth asked in surprise before gagging in disgust. "No. Why would I ever do that? I'm not even old enough for that stuff yet."
"Okay." Natsu commented uncomfortably before he then added. "Beth looked at the guy in awe and then she's back to herself once Kagura hit her head."
"Sounds like a Magical effect to me." Risley thought aloud.
"Charm Magic?" Araña said to Kagura in a dead pan.
"Definitely Charm Magic." Kagura agreed as she began to unsheathe her sword, Archenemy.
"Wait, hold up!" The blonde girl whispered to the group in alarm which caught their attention. "If this guy's a crook, it would probably be best to see what else he's doing first and then turn him into the Rune Knights."
Trading looks, Natsu, Beth, and Happy shrugged while the others nodded in agreement. Sheathing her sword, Kagura turned to the blonde and asked. "Would you like to help us out?"
Showing a vindictive grin, the blonde replied. "Yeah!"
Hargeon Town's Marina, Later at Night
With the girls, including the blonde Celestial Spirit Wizard Lucy, attending Salamander's yacht party, Natsu and Happy stood back at the docks for the ship to come back, one way or another to finish the job. While Natsu didn't like leaving his friends to handle Salamander on their own as a start, he trusted them all to take of themselves and he thankfully didn't have to wait long when he saw the yacht move back to port from what was clearly the combined Gravity Change Magic Power of both Kagura and Risley. Once that was taken care of, he and Happy saw Lucy and Beth leading the other party attendees off the ship. Running straight towards them, he turned to Lucy and asked. "So, what was the idiot really doing?"
"He was going to sell all these women into slavery!" Lucy informed in clear anger at the very idea.
Beth interjected with a savage grin. "The others are warming him up just for you, Natsu! Make him hurt!"
He then ran straight into the yacht and was quick to deliver a flaming punch at Salamander in the face upon seeing him which blew the conman straight off the yacht and into town.
"Crap!" One of Salamander's obvious flunkies yelped in terror. "That freak took out Bora so fast!"
"Bora?" Kagura asked in confusion as she traded similar looks with her friends at the mention of the Titan Nose reject before turning to the henchmen with a meaningful glare. "That wasn't Salamander?"
"Uh, shouldn't you already know?" Another lacky asked back. "You girls are from Mermaid Heel, right? Don't you already hang out with the real fire eater?"
"Fire eater?" Natsu wondered in confusion before saying in annoyance. "What are you talking about? I'm the only Fire Dragon Slayer here!"
The goons then gasped in fright. "It's the real Salamander!" Then attempted to run away before getting surrounded by the Rune Knights leaving a confused Natsu and Mermaid Heel group to ponder what they were talking about before Araña's eyes widened in surprise and she exclaimed. "The Salamander rumors were about Natsu this whole time?!"
"What?!" Natsu yelped in shock. "Since when was that a thing?!"
Momentarily stunned for a moment, Kagura merely shrugged and giggled as she then walked over to Natsu and said to him. "Well, at least you're getting famous, Natsu."
Showing a toothy grin, Natsu replied. "I guess I am."
The two then kissed each other intensely much to Risley and Araña's amusement.
Had a thought about this from looking up the restaurant Mermaid Heel owns in the Fairy Girls spin-off, the light novel that featured male Wizards attending the guild in dresses as a kind of exchange program, and the fact that Kinana originally started as an employee of the Fairy Tail guildhall before officially becoming a guild member eventually. Really wish that we can finally see Mermaid Heel's guild master, but I guess so long as Fairy Tail continues in some form, it remains to be seen. I admittedly did get some doubt when I talked about this idea with an associate on FFN, but I liked the idea well enough and I can imagine that it wouldn't exactly tarnish Mermaid Heel's reputation if an employee like Natsu in this AU isn't waiting tables in a dress, if you know what I mean. As I understand it, there's a similar story on FFN called The Dragon and the Mermaids, even if it didn't really capture my interest, so I guess it is how it is.
I know it wasn't really said when Kagura joined Mermaid Heel, or when Beth immigrated from the Western Continent to Ishgar, but in this, the former's been around for as long as Natsu in canon Fairy Tail at least and I suppose it can be surmised from this depiction that Beth moved to Fiore at a young age. I kind of had half a mind to add Araña and maybe Risley to the pairing, but decided to hold them back so that Beth could be added to the FFN character selection for the sake of argument. I can understand why she's probably not that major, though. In X791 where she's sixteen, she looks pretty much like a kid compared to Sherria who's a year younger, but has curves in all the right places.