Are you afraid that people are so easily going to forget that the facade of fantasy is in place here and start imagining themselves in romantic situations with actual children?
Both of the twins have gone through a hundreds situations far more harrowing and emotionally scarring themselves than a consenting romantic relationship with a stable 'human' being. They're on the precipice of adulthood/considered adults by some of our real world standards already. (And from an emotional standpoint they both seem abnormally well adjusted and 'adult' already.) Much less in a high fantasy setting taking place far in the relative past where most people don't seem to survive their fourties, being exposed to such realities was far more common and acceptable in our own world.
There's an almost accusatory tone to most of this post where I doubt the OP is prone to the obvious fear you're projecting here. Heck, I'd put money that the OP is around the age of 16 themselves.
On topic:
I don't see the hug as indicative at all. Alisae's musings on Thancred's line is certainly suspect, but a bit of a leap to say she's talking about flirting with Lyse. And I don't see Alphinaud X Estinien at all.
