I'm not gigaexpert on this topic, but isn't this description pretty accurate?: What is the difference between polyamory and open relationships? In an open relationship, you're free to have sex with other people but stay emotionally committed to only one primary partner. In a polyamorous relationship, you're committed to loving multiple partners equally. I understand that its different for everyone, but it applies pretty well to SH and her general behaviour through earlier acts(again she denies any poly proposal even for Karlach and Astarion).
In what world does her general behavior in act 1 and act 2 imply she's open/poly, how is that the conclusion you've come to after all that's been said and done here? And why would you even use something that proves the exact opposite as an argument for that? I don't even have to prove you wrong anymore, you're doing it yourself.
