I like how Tiffa doesn't deny that they're cow udders.

Same.

And no one wonders why Yuffie has a penis?

FoofyOne said:
And no one wonders why Yuffie has a penis?

it's part of a doujin, first pages explain why.

name of doujin and/or links?

Source: http://g.e-hentai.org/g/19845/2d65d63aa1/

...what was the point of her putting out her breasts if she was going to suck on it haha