If we start taking everything from Homestuck literally (something I doubt Hussie intended us to do), we might as well assume that, based on the fact that Equius' trolltag is CentaursTesticle, hoofbeasts (and possibly other Trollian animals) reproduce the same way humans do, in which case it doesn't make sense for Trolls to be so confused by human biology and reproduction.

You just poked a giant hole in the fabric of Homestuck.

I hope you’re happy.

-Mod L