I'm pretty sure most Imgflippers thought Grumpy Cat was a boy.

Tardar Sauce (the cat who plays Grumpy Cat) and Grumpy Cat (the character) are not the same cat. One is real, the other is fictional. Just because Tardar Sauce is female doesn't mean Grumpy Cat is.

Oh good, because if Grumpy Cat was a girl, this would be weird: https://imgflip.com/i/13qpp9

I don't really care, i think she's funny anyways.