"Mind if we switch things up a bit?" Qyreia asked, stretching her arms and wiping the sweat from her brow in one motion. A quick glance showed how intently the Onderonian was looking at her, partly out of martial interest, but also out of a baser instinct. My eyes are up here, she thought, thankful that she had underwear beneath the tight shirt.
"What did you have in mind?" Almost as though she had been planning it, the mercenary walked over to the weapons racks and grabbed what appeared to be a rifle. "I thought we said no guns."
"Look closer, Celevon."
Hefting the rifle for closer examination, it proved to be a softened dummy rifle, used for close-quarters training and without any of the normal shooting apparatuses. "Hm. Alright then, but only if I can pick my own weapon too."
"Be my guest," she said, motioning toward the assortment that lined the walls. "Just nothing sharp, okay?"
"What about spikes?" he joked, long since having broken his usual icy facade in the face of the amiable sparring partner.
"Pointy is the same as sharp," she responded, sticking out her tongue chidingly. "Come on. I wanna kick your choobs again."
Let's see how you handle this, then, he thought as he hefted a weighted practice sword from the motley selection. It would sting - could even break a bone if one were to swing hard enough - and had the right balance for what he was used to. "This alright?"
"Sure, if you think that'll be enough."
"You sure talk big for someone so short," Celevon said as he returned to the mat.
"What can I say? I got my sassy pants on!"
His eyes traveled to her unflattering sweatpants and grinned. "That's not what I was looking at when I came in here."
Qyreia's face turned a slightly darker shade of red. "H-hush you. Are you trying to fight or buy me a drink?"
"Maybe both," he said, lunging forward and catching the flustered Zeltron off-guard.
With barely enough time to react, the Sadowan clumsily threw up the dummy rifle to block the vertical swing from the training blade. It struck with an unexpected weight to it that seamlessly melted away as Celevon drew the sword back for a thrust that, to his surprise, his opponent deflected much more easily than the initial assault. Chocking it up to the Zeltron's mind being back in the fight, he continued the flow of attacks fluidly, making a high slash from the left followed by a low cut from the right. Every maneuver was carefully thought out. Every attack was seamlessly succeeded by another to keep the woman on the defense.
And every time, she either blocked or deflected him with the fake blaster.
The movements were not particularly graceful, as Qyreia shifted her posture as much to accommodate the weapon's weight as avoid the human's weapon. However, the Assassin couldn't argue the haphazard technique's effectiveness, no matter how much it confounded him. His arm never tired, yet as time passed, his attacks seemed to have less impact. His speed never faltered, yet the Zeltron was no longer retreating. She was advancing.
After a particularly wide deflection, she followed up with a muzzle-thump aimed for his sternum which he only narrowly avoided. He made a slash at shoulder level, only to have it bumped away and her buttstock come in a harsh swipe that connected with his ribs. That'll leave a mark, he thought as he withdrew to a safe distance, opting to observe his opponent, using the sword's superior reach to keep Qyreia at bay. Let's make this interesting. While Celevon was once again on the attack, Qyreia thought it odd that his sword seemed so defensively postured. Testing his intent with a thrust, he turned the rifle's momentum aside just as she'd expected. What she hadn't expected was the lightning-fast kick that caught the side of her knee, throwing off her balance before a second kick sent her sprawling backward, the dummy rifle falling to the ground nearby.
Not one to let the advantage slip by, Celevon leaped forward to land with his feet planted to either side of the Zeltron, sword postured for a coup-de-grace thrust. "Yield."
"You cheated. That wasn't using the weapon."
"That's combat, beautiful."
His opponent's expression twisted into a grimace just before she launched her foot from the ground to make solid contact with his undefended groin. The sword went limp in his hands at the surprise attack, allowing Qyreia to lurch to the side and, taking the barrel of her rifle in hand, swung the thing in a sickening arc like a club, connecting once more into Celevon's rib cage. In short order, the human was sent in a heap to the ground, dropping the sword out of his supine reach. Before he could react, he felt a sudden weight on him as the Zeltron threw herself on top of him to straddle his chest, one arm pinioning his throat with the other ready to hammer his face with a balled fist.
"You cheated," he croaked from beneath her weight.
"That's combat, Nipples," she said, smiling and panting for air. "I told you this is how I fight."
"Fair enough."
He eyed her for a long moment, sweat dripping from her face, before loudly patting at the mat in surrender. While not particularly heavy, feeling the weight lifted from his windpipe was a welcome reprieve. Feeling her hands on his bare chest brought a different reaction. It seemed all too natural to set his hands on her hips.
"Unless you want your dangly-bits obliterated again," Qyreia said sternly when she felt his grip start sliding down, "I suggest you reorient your hands to someplace else."
"Sorry. Got caught up in the moment." His eyes wandered again, noting an odd scent that lingered over the rubbery sterile smell of the practice mats. Lavender and... starship fuel? "So... about that drink?"
"So long as you don't get any funny ideas, I'm game." She smacked his forehead as he was about to rise. "And keep your eyes above the neckline. Deal?"
He chuckled. "We have an accord."
Syntax
These are two independent clauses. They can stand as two complete sentences, so a full stop or semicolon would be more appropriate than the em dash. Also, a minor mistake with "twitching hand that indicating": The steely glare and twitching hand that indicated she was rethinking on whether or not to shoot him made Celevon drop his flippant attitude. Clearly, the woman was in no mood for his more cheeky side.
Story
This dialogue is a bit expositional. It reads more like an informational poster than a part of the conversation. In this case, the information provided is already present in the venue description, so a few snappy words would have sufficed to remind the reader of the rules. To avoid expositional dialogue, ask yourself if the information provided is already known to the reader and the two characters speaking. If so, it can probably be cut or trimmed down.
This contains the essential ingredients of an opening post: an introduction to the characters, a pinch of action and a hint of their states of mind. From here, you could expand on the context of the battle and the reason for them being here (beyond wanting to train). Since this is a 2/2 match, it is also a good idea to get into the meat of the fighting in the first post, otherwise you will only have the final post to write some action.