1. The Captainís Girl (Mirror Universe)
By the mid 22nd century, the Terran Empire has conquered the vulcans, andorians, and a number of other nearby species. Some members of these conquered races serve in Starfleet, hoping to earn a measure of independence and respect among the humans. Others have gone into open rebellion against the empire. This rebellion is eroding the imperial fleet and causing hostility towards the aliens in the fleet. Many become subservient to their human superiors, becoming consorts in addition to their regular duties.
When the Imperial starship Intrepid is attacked by rebels, their captain is killed and the ship's new first officer takes command. In their anger, many of the crew feel that the ship's alien helmsmen, who was the captain's consort, was working with the rebels to ambush the ship. The crew expects the new captain to kill her, but instead he claims her as his own consort.
Rather than find a cruel, prejudiced superior, the helmsmen finds herself with a captain who is level headed. She even senses a certain degree of compassion from him. With the proper influence, perhaps he could be motivated to help the rebels and prevent the destruction of her race. For that to happen though, he will have to stay alive. In the Imperial fleet, the perception of weakness invites assassination. If power were to transition a third time, the young helmsmen would likely find her fate heading down a much darker path.
For this story, I'm looking to do a story set in Star Trek's Mirror Universe. Instead of the Federation as we know it, people live in a much more warlike empire. I'm looking to play a character who can be ruthless when the situation calls for it, but is more composed than many of his peers. He would be entering a dom/sub relationship with your character, though he doesn't see her as inferior because of her species. He simply outranks her. I was picturing the helmsmen to be a vulcan, but really any alien would work. I'm flexible.
2. Deconstructing a Vulcan
A small Starfleet science vessel unknowingly enters the territory of Ritori, a race that look human, though they have powerful telepathic abilities and are strongly territorial. A Ritori vessel disables the science ship, and the ship's young captain is given the right to claim a trophy from the mission to signify his success. After looking over the Starfleet database, he selects a young vulcan officer, as he is fascinated by their lack of emotion. The rest of the ship is allowed to leave Ritori space, but she will remain his. Using his own abilities, he is determined to break down her walls and force her to feel what he wishes her to feel, fear of letting him down, desire for him, and pleasure at his touch. By the time he is finished, he is convinced the young woman will make the perfect status symbol.
This story really appeals to me as more than just smut. I think it would be a lot of fun to explore what it would be like to be someone who has never felt emotion and suddenly find the walls that prevent such emotions falling apart. This would be her first time feeling desire, lust, and even pleasure. Eventually, I would like to see her status change from captive to partner as the two try to carve out a place for themselves, even as they are surrounded by enemies.