The Technomancer
card-carrying scientician
So RockPaperShotgun did a dive on the code in Rimworld and discovered some of the ways in which the relationship system is governed
https://www.rockpapershotgun.com/2016/11/02/rimworld-code-analysis/
And the creator jumped into the comments with this gem:
Now, I'm absolutely certain that this thread is going to be filled with "but women pursuing older men is how the real world works!" and "but men initiating more relationships is how the real world works!" I think that's bullshit for myriad reasons but can we at least acknowledge that its fucked up that there are no bisexual men and no straight women?
Damnit. I was considering buying this when it left EA also, but the dev's reaction doesn't particularly instill confidence that they even know why this is a problem
https://www.rockpapershotgun.com/2016/11/02/rimworld-code-analysis/
Returning to Reed, we can see that the pick-up lines don’t get her down. She receives no penalty to her mood for being barraged by come-ons. But the two men, Rob and Boots, feel differently. They have a near-permanent mood and relationship penalty for Reed, because they keep asking her out, and keep getting rebuffed. But it’s not really their fault – Rob and Boots can’t stop hitting on her because they’re men, and because she’s just so gosh-darned pretty. More precisely, that’s how they’ve been programmed.
In other words, female pawns are about eight times less likely to try and start a romantic relationship. Granted, this is not the only factor – other elements include presence or absence of an existing romantic partner, and how they feel about said partner. However, this single check on gender has such a profound effect that it makes female-initiated romance attempts incredibly rare.
There are no straight women in RimWorld, as in, there are no women only attracted to men. Instead, every single non-gay woman in the game has some chance of being attracted to another woman.
Notice that there’s only two possible orientations for men, gay or straight. In RimWorld, there are no bisexual men, only gay or straight men; there are no straight women, only gay or bisexual women.
In RimWorld, male pawns will always find pawns between 20 and their own age attractive. If the male pawn in question is under 20, that doesn’t make a difference – because it’ll check the “lower” bound first, they’re guaranteed to find a 20-year-old attractive. This explains why Rob (age 32) and Boots (age 17) keep trying to ask out Reed (age 23). But, since the same code doesn’t check for relative age, 17-year-old Boots wouldn’t actually find a fellow 17-year-old teenager all that attractive. There’s also a minimum age for attraction, 16 years old, and a maximum age, any pawn 15 years older than themselves. So in this case, Boots wouldn’t find any woman over the age of 32, or any woman under age 16, attractive.
On the other hand, women overwhelmingly prefer partners older than them. And, unlike for men, there’s no firm cutoff for pawns that are “too old”: even pawns 40 years older than the woman in question have a chance of being perceived as attractive. Contrast this to the calculation for men, where pawns 15 years older than them have absolutely no chance.

On top of that, what RimWorld doesn’t model is as important as what it does. Remember how constantly being hit on and rebuffing people doesn’t lead to a mood penalty, only a reduced opinion of the person pursuing? In daily life, the feeling of having to constantly turn people down is not a nice feeling. But these negative feelings are only reflected mechanically for those being rejected, and because of the way romance initiation is handled, you end up having to cater for the sad rejected men, rather than the women who are always having to turn away these unwanted encounters.
We could label that behaviour a bug, perhaps. But those are just the surface symptoms. Those are the easily-noticed, in-game consequences of a system whose base structure has literally encoded assumptions about how men and women operate. Now, representation is a tricky subject, and we will probably never create a perfect model of romantic behaviour.
But the problem with this model isn’t that it’s flawed. It’s that it’s flawed in a way that perfectly mirrors existing sexist expectations of romance, with such specificity that it is hard to view it as unintentional . And if it is unintentional it is on us to ask what this system is trying to show. What are the possibilities that it allows? What is RimWorld setting as the boundaries of possibility?
And the creator jumped into the comments with this gem:

Now, I'm absolutely certain that this thread is going to be filled with "but women pursuing older men is how the real world works!" and "but men initiating more relationships is how the real world works!" I think that's bullshit for myriad reasons but can we at least acknowledge that its fucked up that there are no bisexual men and no straight women?
Damnit. I was considering buying this when it left EA also, but the dev's reaction doesn't particularly instill confidence that they even know why this is a problem