@Niara
Sorry if I didn't explain my perspective clearly. What I don't like is that a character is created to attempt to fit everyone's preferences. I understand that Bisexual people exist. I wasn't trying to make you feel like I think you don't. I apologize for making it sound as if you aren't real.
I'm an author. I create characters all the time. For me, a character is special; like my own child. Okay, maybe not that special.
But the point is that when I create a character, I create the person's background, preferences; every aspect of that character. In the end, when I put them together with other characters, they tell me their story and I write it down. I often have some concept for a story and an idea of where I want the story to go, but then the characters might actually go in a whole different direction because they are living, breathing characters that I've created. A good author respects the characters they create. If they change them, they do so with care and love and respect. That's what makes good character creation and development.
So, I might create Hala, a bisexual half-elf rogue who has had a difficult past on the streets of Waterdeep. She typically identifies herself as a female even though she is a male. She hates fish, detests humans, loves dwarves, tolerates halflings, is quirky, funny, and generally people like her. I like Hala. She's a fun character to me. I may be heterosexual, and I may not truly understand how bisexual's feel and think, but I have carefully crafted Hala and I respect her character.
Now, imagine, I put her in a game and a heterosexual person is playing the game. They really like Hala. They think Hala is a woman. They romance her. They find out she's actually a man. Suddenly, the player is screaming for me to make it so Hala is actually a woman. They are super upset because they were really connecting with Hala, but when they found out she was a he they were so upset that they no longer even like the entire game. And so, in an effort to please everyone, I make it so that if a player chooses to play as a heterosexual male, Hala will be a woman. If they choose to be a bisexual, Hala will be who she was originally intended to be.
Is everyone happy? Hmmm. Maybe. But probably not. Why? Because that still won't likely fit everyone's fantasy. A new player is playing the game and romances Hala. This time, the player is a homosexual female romancing Hala because she thinks Hala is a woman. She learns Hala is actually a man who has chosen the female gender. Now this player is thoroughly upset and complaining. So now I have to create yet another set of parameters to make everyone happy. I have to make it so that the player can choose to be homosexual male, homosexual female, bisexual, heterosexual male, heterosexual female and for each one of these options I need to now alter Hala so that Hala will fit whatever romantic fantasy mold for each type of person.
My point is this. Hala went from being a bisexual half-elf rogue who is sexually a male to a "whatever-the-player's-preference-is" character. Suddenly, I have to craft new elements of her backstory just to fit each of the preferences. Whereas maybe Hala was married to a bisexual female in the past, because the player chose to be a heterosexual male, Hala must now have been married to a heterosexual man. Over and over again, this one, single character must undergo various personality and character transformations all because I am trying to please every player that exists. The next thing you know, Hala is no longer even really Hala.
So, what I'm saying is, if Wyll is bisexual, make him bisexual. If Astarion is, then so be it. If Shadowheart is heterosexual, then have her heterosexual. If Lae'zel is homosexual, then just have her be homosexual. Don't try to make every character fulfill every player's fantasy wish-list. Why? Because the more you do that, the more generic every character becomes. They are no longer a person with true preferences and personality.
