Like pac-man esc. pixelated? I wanted to make a 2 girls 1 cup parody or something.

Of course. There's plenty of pixel porn here.
Just make sure to read the Terms of Service for any banned porn, though. And keep in mind, if it doesn't break any of the rules on the ToS, it's allowed on here.

Question... why would you WANT a parody of 2 girls 1 cup?!

If you're referring to "pixel art", yes it is. Pixel Art is a legitimate art style and all art styles are allowed.

Yes as long as it is of good quality.