1. This is a video game, no matter how real it feels, we have to understand SH (or any other character) won't pop out of the monitor, so we can have some kind of Blade Runner 2049 experience. But that doesn't mean we can't fully involve ourselves into the story and have the best roll-play experience ever.
2. This (among other related topics) can either go in one of 2 directions: Larian could listen to the community and allow this dynamic we want; or they could pretend none of this is happening and everything (at least for this matter) remains the same.
So, with that in mind, let's continue...
There should be options for both perspectives (poly and mono). It is not like we are demanding something that hasn't been established by the game (both things are possible and allowed: being poly or mono), but we are arguing about how the game bottlenecks or narrows at some points, basically forcing you to take just one.
Let's gather the evidences we have so far:
1. SH was abused during her Shar life, she was "forced" to do things in the name of Shar. Like a brainwashed religious person. So, if she had casual non-sentimental carnal relations with other Shar followers, it was for the name of Shar, not by willing. She "didn't care" since it was Shar willing.
2. Halsin is a terrible-written character, who's primary purpose is being a forced sexual joke. Always harrasing the MC. You can deny everyone else, but him. There is always the option for an open sexual-relation with him. You can deny everyone joining your party, but him... again. And literally most of the things he adds to the game are things that one can figure out without him.
3. SH will reject being a spare-lover with any other companion but Halsin (suspicious). Why can't she allow someone else? Or be consistent and reject everyone? It's like saying, "I don't want anything casual and forced anymore, I want you full... but ummm let's give Halsin a chance, so it would be easier to approach that wild bear later"
4. She goes with all the "you and only you" BS, and how she found herself with you by her side... but after finishing her storyline there is that banter where she is LITERALLY flirting with Halsin like WTF? Can't the game tell I didn't sleep with anyone else? It just breaks the roll-play experience one is following
5. It is true that going to the twins (and knowing the context) you shouldn't expect more of her if you decide to sleep with them (even Halsin). But why isn't there a voice line to reject the idea if you are following a mono path?
It is more than obvious that someone decide to put his little fetish in the game and wrap it round HS and Halsin. And IDK maybe this person dreams with people watching him, so we are "watching him" through Halsin. Disgusting...
I really like this game, honestly, it drags you to experience the full adventure (in all senses), but when you are building something, following certain paths and then something like this happens is just... it feels odd, like something's missing.
So, what options we have? Kill Halsin? Let the goblins kill him? Never talk you him? Let the shadow-lands with the curse?
That just means narrowing the game more, having less options...
So, we ignore all that, we don't talk and reject those twins? We get rid of Halsin right after SH learns to swim? Yeah, it could work, but we are just pretending. The moment we include Halsin that banter will pop-out. The moment we talk to the twins we know the only answer SH give no matter how mono the relation was. Worst if Halsin is included, like okay we are open to snacks but only if we both feel comfortable, oh look! Halsin wants to join... how dare you say no? DISAPPROVE! Like apparently if you go poly you are forced to like the bear, otherwise people dislike you.
And even worst, okay you decide to take Halsin, once into the room you are just a snack, Halsin is the real king in the house. And suddenly SH reveals she's been dreaming about him (and was lively), even if she literally spent the last night with you, and until that moment you've been playing mono. Consistency people, like please.
Well... finally, how can Larian fix all this? I won't go deep (not like Halsin, jk jk) But here are some ideas, simple ideas (is not a big topic that requires hours and days of thinking):
1. Fully allow mono and poly, and respect the players decisions. Is a roll-play game, the system should react according to the player's decisions, not the system deliberately telling the player what they have to choose.
2. You went mono? You rejected Halsin n-times before the end of HS arc? Furthermore, you didn't cheat with her? Then don't trigger the dam banter
3. Allow people to reject Halsin from joining your party (if he doesn't add anything for you), we don't need to ignore him or kill him, just let us say NO
4. Allow people to be poly with HS and different companions, not only Halsin (unless you actually want to respect her story, then don't allow this option with any companion including Halsin)
5. If you went full mono and for whatever reason decided to talk with the twins, show SH disapproval by dialog or a simple "SH disapproves" message... so you are respecting what the player built and the consequences of being horny all of a sudden
6. If you decide to go poly (and according to point 4), is a mutual agreement, so... if you get to the twins and (unless your spare-lover is Halsin) don't force me to accept his offer and don't show SH disapproval. You want, I don't, I only want the twins (you want them too), but I don't need Halsin, so (game) respect that.
7. A similar scenario (point 6), but now you are "dating" Halsin, well... NOW show the disapproval. You are eating that meat, but SH can't? Come on dude...
8. Now let's say you are poly but also a son of a gun and decide to cheat on SH (you didn't ask her). First, don't say that "you and only you BS". Second now show that banter. Third, show her excitement in the brothel when Halsin decides to join, and of course show the disapproval if you refuse. You can be a bitch, but she can't? Again, come on dude...
9. And finally (but probably not last), you were mono, but then you cheat then repeat the point 8.
There...of course there could be more scenarios, but I think these 9 points sums almost everything. So you respect different paths, different decisions, everyone is happy. If someone gets to a scenario they didn't like, well, that's the player's fault. Don't want SH to be a whore? Then why are you behaving like one (acting like a second Halsin).
So I really hope they fix all this, along with other companions problems. I am a developer my self. We once changed a client system in the company I work for, we thought it would be for the best, but no... a lot of clients started to sent bad reviews and complains, they wanted the old system back, but there were those who wanted the new system to stay... what did we do? Simple, we deployed both options, and everyone's happy in that regard...
I think we should do as Madguise said and put a ticket for Larian about this topic (since more and more people keep complaining) and hope for the best.
Anyway, thanks for reading, and sorry for my poor lexicon.