![wolf girl with you uncensor patch wolf girl with you uncensor patch](https://i.ytimg.com/vi/MFUCuKd1Cig/hqdefault.jpg)
Same goes for vaginas, though in some hentai they don't even dye it leaving a skin color.
![wolf girl with you uncensor patch wolf girl with you uncensor patch](https://igg-games.com/wp-content/uploads/2019/10/How-to-Raise-a-Wolf-Girl-PC-Crack.jpg)
The reason it appears in show is an unwritten rule for all anime and hentai because in japanese representation this is how perfect female body should look like and I doubt there would be exceptions even if a girl is color blue or green. Just google some latin girls right now and you'll see there's no pink at all, that's how anatomy works. Every authentic source declares that nipple color is primarily related of a skin tone, and this is exponential correlation. Pink nipples are nice an artistic (sometimes), but they are just scientifically incorrect.