1. Sith Academy
Darth Malak has set up a sith academy on Korriban. Students with the power to use the force are brought to learn the dark side in service to their sith masters. My character was recruited from the edge of the sith empire. He has the ability to use the dark side, but he has an upbringing that also allows him to touch the light. His instructors have been told to mold that out of him, to make him into a weapon Lord Malak can use.
Many of the most promising students are given perks the other students are not, including a slave to tend to their needs and desires. The young woman they select for my character has seen her people slaughtered by the sith, but she has learned that challenging their authority means only suffering for her and her fellow captives. She is assigned to the potential sith, expecting nothing more than pain and abuse, but finds him gentle, caring. On his own, she knows his teachers will force that out of him, turning him into another killer like the ones who destroyed her world. But as he comes to care for her, she realizes she might be able to change his fate.
2. The Governor's Daughter
The attack vessels arrived on her world without warning. Her people were proud and determined, but they were no match for the relentless power of the sith. Before anyone could really react to what was happening, the sith were in the capital and had captured the royal family. The young sith lord in charge of the invasion assured them that he would keep his people from harming civilians as long as the governor kept his people from defying the sith empire
He had planned to leave it at that, but when he meets the governor's daughter, he senses a flicker of the force within her. It is completely undeveloped, but she has potential. Rather than detain her with her family, he claims her as his trophy of war. If she can be turned, she will be a powerful ally. If not, seeing her as a captive slave will help to remind her people that their days of independence are over.
3. Revan and Bastila
I'm picturing a world set after KOTOR 1, where Bastila fought for the light side, but Revan fell to the dark side and destroyed the jedi fleet. Bastila now finds herself a captive of the sith order, and Revan is determined to shape her into his perfect apprentice and servant. There are a lot of ways this could go and a lot of tactics he could use, so details would need to be discussed with a partner.