So I generated a pet, and its colors did not match how I designed it. Why did this happen? Here's a pic for reference:

What I wanted it to look like:


What it turned out to be:


Me and Candela both had this problem as we generated a male and a female.

Yes:

What he had to look like:


What he's looking now:

When generating pets, they can get what's called a color swing. This means that the color you choose, may not be the color you necessarily get.

You could want a pastel and end up getting a washed out solution to it. You could want a bright neon, and get a dull solution to it. Sometimes the colors will be completely wacky, such as you choosing blue, and it turning out yellow instead.

This also happens with themed pets, where despite the colors being very very similar, the color swing does make it where it's very unlikely for two themes of the same kind to have the same color hexes.
Using pet dyes also results in color swing. Lesser pet dyes are less accurate in dying a pet than greater pet dyes.

Color swing with essences is more severe depending on the essence you use. Regulars have the worst color swing, and the color swing gets increasingly better/the colors you pick are more accurate, the better the essence type you use.
Assuming you used Regular essences, Regular essences, in their description are described as having fairly accurate colors.
Enhanced essences are described as being mostly accurate with colors.
Mystical and Divine essences are described as being extremely accurate with colors.

So, what happened for you both is normal, though frustrating.

Oh, thanks. I guess I never thought about that.