A young, successful woman goes to bed in her own bed, but wakes up to find herself on a harsh alien world. Her only companion is an attractive young man who informs her that she has been taken from earth so that a handful of powerful aliens can hunt them for sport. The two of them work together to evade capture, but eventually she is taken. Once she is captured, she serves as a slave for one of the aliens, humiliating herself to please him however he desires. This treatment goes on for a few days until she wakes up to again find herself on a different alien environment with her human companion. The cycle repeats itself again and again.
I'm looking for something that would be 50% the two human characters struggling to survive and avoid capture in a harsh environment, slowly growing closer in the process. The other 50% would be her time as a captive of one of the aliens, acting as a slave, pet, or sometimes perhaps a toy to him. Advanced alien technology might be able to freeze her in place, make her serve as a decoration, or make her burn with desire. Lots of kinks could be worked out with a partner.
The twist would be that the alien captor and her human lover are the same being. The alien is capable of changing shapes and wishes to experience a romantic relationship and a master/slave relationship with a human female.