![An edited screenshot of a section of code in a pet file in Petz. The text is green on a black background. A section of the text is instead highlighted in cyan and reads 0 0 [question mark] [question mark].](/images/nonbinary.png "Non-binary to a new, literal level.")
I'm far from the first person to talk about Petz's non-binary petz (I'm thinking of this page over at Unique Petz, mostly), but I as a cassgender person find the phenomenon so charming that I felt the need to invent a whole new category of Petz help just to talk about little quirks like this. I also have a couple of Pride cliques referencing this phenomenon's results, which I talked about on the WordPress blog way back when I first made them, so I figured maybe I'd go more in-depth because of that.
So, without further ado, non-binary petz!
The usual meaning of the term "non-binary" is "a gender outside the societal binary of male and female". These petz technically fall under this term, but it also doubles as a reference to the fact that their genders fall outside of the literal-binary-as-in-code system of female and male that Petz's code uses. Basically, non-binary petz are a Secret Third Gender for Petz.
Because they're technically female in-game (keep reading for more on that), some people refer to these petz as lesbian instead. Both intepretations are valid—I just use "non-binary" because it's what Petz utilities tend to use, and it's humorously literal to me.
Petz uses a binary system in a petfile's code to track a pet's gender. 01 is male, and usually 00 is female. (You can find this for yourself through a hex editor, similarly to how you change their favourites — search "magic" the same way and go to the third result instead of the fourth, and it's the two bytes directly after that, typically reading 00 00 or 00 01.)
However, the game doesn't actually make sure a pet file has 01 or 00. It, in fact, lets you use any old byte in that gender space.
Ordinarily, 00 or 01 are the only two values that appear for gender, and you need to modify files yourself to get anything else... but the advent of tools like PetzA and its ability to change a pet's gender made it more likely that things get glitchy, so it's become more frequent lately. Prism's fork of PetzA even lets you Non-Binary Beam your petz right from the menu!
Two major things come to mind when I think of effects of non-binary petz in the game itself. For starters, the game doesn't actually consider only 00 female, but rather anything but 01, so any non-binary petz will show up on the carrying case with the pink, "female" icon. This is what makes it so hard to tell unless you use a tool like PetzChecker, and what gives rise to the lesbian interpretation.
Secondly, as a consequence, the game never actually checks that a pet with 00 is only able to mate and have babies with a pet that's 01. It just checks that the two pet's genders are different from each other... meaning non-binary petz can mate with both male and female petz, or other non-binary petz. They can equally become pregnant or make female petz pregnant.
There's a few situations that can happen where petz of the same gender fall in love, but it isn't always because one is non-binary. Petz can actually just sometimes fall in love with the same gender, occasionally. I once had two lesbian catz named Sparkles and Stars, and both of them came straight from the Adoption Centre, so I doubt either was non-binary.
Petz can remain in love even after one of them undergoes a change in gender, too — I've actually also exploited this before to get petz to stop fighting, as I've discussed on my "Meet the Petz Breed" page for the Chameleon.