- Roman attitudes towards sexuality weren't quite as egalitarian as portrayed here, but all of the Romans left alive are teenagers, and may not yet have been fully indoctrinated into adult mores. Also, the young tend to be less rigid and more accepting of difference when it comes to sexuality and gender in the modern world, so the same may have applied back then, too.
- Not to mention, Roman Britain was quite a bit removed from the center of the Empire's culture. Maybe attitudes were different out on the frontier.
Fridge / Doctor Who S36 E10 "The Eaters of Light"