Xenophilia, or interspecies relationships, would be the most appropriate term. Although Sophia's relationship wasn't consensual, it was forced in the case of the xenomorph, and in the case of the other specimen, it was induced by her pheromones, in addition to the strange substance injected at the farm, and an alien mind in her head whose effects we still don't know. So Sophia's head is a bomb ready to explode at any moment. That's why she can't say no. Sophia will still be curious about bestiality whenever she returns to the farm, but it will be a slow path.