Obviously sexist.
You see it's got six sides, which sounds an awful lot like sex sides
, besides this it's covered in squares… one of the most manly geometric shapes imaginable (I mean, have you ever heard of female squares?) — all that, combined with a strong root in mathematics (a male-dominated science), means that it's sexist!
[/sarc]
Even worse, the word “sex” is Latin for “six”.