shower thought

okokok hear me out
also when I say this I'm talking about biological sex (go LGBTQ and all but we don't play a factor in this question)

So in the terms of chromosomes, X determines female characteristics and/or just being a place holder in chromosomes, and Y determines the development of male genitalia and systems

XX will always be female, and XY is almost always male (because sometimes, rarely, the sex will draw from the singular x instead of the y)

what would a YY be?

like I know chromosomes come (one from each) from each parent, but what if an XY male impregnated an XY female?
There would be a 25% chance in base genetics that their offspring would be YY

Is this the alpha male everyone refers to? /j

My idea of what YY would be reminds me of the joke of Bills at a bar, and at the end Cherno Bill is revealed, exposing his multiple sets of genitalia lmao