They've confirmed that Lae'zel doesn't do monogamy because it's just not a concept to the gith. Astarion seems to have spent the past two centuries seducing victims for his master and when Shadowheart asks if he has anyone special he says something to the effect that Baldur's Gate is "full of sweethearts." So it's clear that commitment hasn't been a thing for him but part of that is likely because of his living arrangement. I'm hoping that, being free, he'll have some relationship flexibility but I can easily see Larian deciding that he's for fun but that's it. Which would be a real shame, imo.
I can definitely see Gale being interesting in that regard. I feel like if he had a facebook profile his relationship status would permanently be set to "it's complicated." I can see it being a struggle for him but he seems like the type who would eventually commit, either way.
Yeah the morning after the party I touched bases with Lae'zel and after hearing her what she said about the other companion she decided to spend the night was amazing honestly. I love her to bits and I hope she doesn't change in that regard because I just love there being this character in my party that's so free and to the point about that stuff.
In Astarion's case, I have a gut feeling he'll be able to steer a certain way down the line just given some of his dialogue and facial expressions but I'm also just being hopeful. I feel like he's a special case because he's absolutely having the time of his life with this newfound freedom the tadpole is giving him, so it feels natural for him to want that sort of intimacy and to be fluid with his partners. Although, if you turn him down he doesn't go to anyone else that night so there's that to think on. (He says it himself that Gale's blood tastes like bile and I can't imagine him wanting to sleep with a Monster Hunter like Wyll. Lae'zel would literally kill him and I'm not too sure and I'm not too sure about Shadowheart.) Anyways, I get so many mixed signals from him. He's very flirtatious and comes to you at the party asking if you would be willing to indulge him in having some fun, but if you tell him essentially, "I'm just here for the transaction" there's some disappointment in his response. He also has all of these moments where he 's put in these vulnerable states where we're allowed to console him that make me think just
maybe there might be a possibility for something more. Who knows honestly.