Peeked at your code, because if the variable(s) in question were boolean (true/false) that’s a simple fix. But it’s actually a string (orientation = “male”) with more strings as pronouns for the genderflipping neighbor.
Booleans make things less buggy in general (as CJW has explained a few times). And incidentally, they can also lend themselves to less typing… instead of
*if met_sarah = true
or
*if met_sarah = false you can just write
*if met_sarah
or
*if not(met_sarah)
for the same effect.
My own game uses two booleans for orientation: malepref and femalepref (created here, set here and here – search “set malepref” in the latter two files to find the relevant line). Their value is set not in an up-front char-gen question, but when you meet two potential romantic interests. If both are true, the MC is bi. Search “if malepref” to see some of the ways the boolean affects the code.
If you did care about including a bisexual option in your current game, as far as I can see it wouldn’t require much editing – you’ve only used orientation in a couple of places. Just replace the variable “orientation” with two booleans; add a choice to like getting sticky paws on e.g. “Anybody,” in which both booleans are set to true; and change the bits with Sarah from “if orientation = female” to e.g. “if femalepref”.
As for your sexy zombie neighbor, you could either have them default to be e.g. male if you’re bi, or slip in a choice when you’re about to meet them for bi MCs:
*if femalepref and malepref
My neighbor is...
*choice
#...a hot guy.
#...a hot girl.
Just a thought.