No. 1. 
“Among other things. I also am not unmindful that the choice to become drakaina was not Aria’s and that she also feels forced into a pair bonding with me.”

Basil shrugged. “That has been the way for drakaina for thousands of years. Over the millennia, dragons have discovered that while the best way to our hearts might be through our stomachs, the best way to a drakaina’s heart is often found between her legs.”

Darius chuckled. “I don’t know if that’s true or not, but I’m willing to believe.”

“Take it from an old dragon who still finds his mate to be a handful, a well-sated drakaina is a happy drakaina.”

No. 2 (This one is explicit).
He covered her body with his, kneeling between her legs and forcing hers apart. Removing his fingers, he grasped her hip as he guided his hard length into her, driving home in a single push. She was naked on her knees, on the soft earth, a man, a dragon unknown to her pounding into her, forcing her response—her quiet keening and moans providing the melody to his harmonic grunts and groans in perfect rhythm with his thrusting.

This man, this dragon, was a stranger to her and yet she responded to him as if she had been waiting for him all her life. That wasn’t true; it had been many years since she had given away her virginity. Her pussy snugged around his cock as if it had been made for him, for his use, for his pleasure.

He fucked her with a ruthless passion and relentless need. It was as if he, too, felt the flames that threatened to consume her and only their mutual release could save them. The dragon’s desire seemed to know no bounds as over and over he plunged all the way to her depths, before drawing back and driving fiercely home again.

Locking her into place with one arm, he fisted her dark mane with his other hand, bending her neck and turning her head as he captured her mouth with his, his tongue diving deep to sweep through her mouth and slide along her tongue in an imitation of the way his cock slipped and slid in and out of her pussy.

She tried to move, not to get away, but to take back some small part of control of their frenzied coupling, but the dragon wasn’t having it. Her pussy clenched along his staff as she cried out, not yet in ecstasy, but in frustration that he wasn’t giving her what she wanted and needed. He chuckled as he nuzzled her neck, and his cock began to twitch and swell inside her, causing friction even though she was wetter than she had ever been.

“You are mine, drakaina, and I will claim you as such. You cannot escape your fate. You belong to me.”

No 3.
In his mind’s eye, Darius could see the mist rising from Crater Lake as he did each time he felt the portent of things to come. Only this time instead of the mist rising and swirling into nothing to join with the dark clouds above, a drakaina rose from the lake, black scales glimmering in the moonlight. Dark eyes stared back at him as she roared a challenge, spreading her gossamer wings and beating them to lift her from the water. The mist fell all around her, descending back into the lake.

Darius roared an answer to her challenge as he called forth his dragon in a shimmering mist of copper and bronze. The swirl of bright lights and energy only protected the one who was shifting as it rose up and then fell away. After that, the dragon or human it left behind was vulnerable to attack.

He only barely managed to escape the burning breath of the female before she reversed direction and flapped her wings, flying up and away.

He knew this was a dream; knew that it wasn’t real and yet he could feel the fire in his belly. Instead of turning away, which is what he told himself he would do in the waking world, he gave chase. Beating his leathery wings to defy gravity and to give him more speed, Darius gave chase to the beautiful drakaina. She would not escape him.

She flew across the tops of the trees and towards the tops of the snowcapped peaks with Darius in close pursuit. Whoever had deemed the mating urge “Eternal Fire” had spoken from experience. It seemed that instead of blood, wildfire coursed through his veins, burning him from within and making him feel invincible.

The female feinted and banked with Darius in pursuit, each beat of his enormous wings bringing her closer to his grasp. She dipped down low, dragging her claws across the tops of the trees, slowing her advance only by a fraction, but that tiny, almost infinitesimal decrease in speed was all that Darius needed. 

He flew up and over her as he extended his back legs and used his talons to wrap around the base of her wings, preventing her from escaping and leaving her at his mercy. He held her in such a way that she could not turn and breathe her deadly flame at him. There was strength and power in her body, but a lack of honed fighting skills had left her vulnerable and Darius had seized the day.

Darius’ hold was tight but not enough to do any real, lasting damage. He shook her briefly, inhaling the sweet scent of her arousal, which permeated the air. She might defy him, but her growing lust confirmed that she, too, was in the grip of the Eternal Fire. 

She roared as the shimmer enveloped them both—his copper and gold merging with her dark aura streaked with red and silver. The unnamed female dragon shifted within his grasp and became human again just before he did as well. In other circumstances, Darius would have longed to place the drakaina over his knee and administer his discipline in a way that would chastise her for running, even as it inflamed her desire.