Nintendo's upcoming "Mario Kart World" is already generating massive buzz ahead of its launch with the next-gen Nintendo Switch 2. But it's not just the new console or game that's got everyone talking – an unexpected star has emerged: a dairy cow.
This bovine buddy, originally just a background NPC in previous titles, has now made the leap to a playable character. Players are loving its adorable design and surprisingly strong performance on the track. But recently, it's not the cow's racing prowess that's gone viral on Japanese social media – it's its... well, its rear end.

Gamers on X (formerly Twitter) shared screenshots showing the cow's backside getting surprisingly grubby during races, sparking a flurry of comments. "That butt is SO dirty!!!!!" and "I love her, but seeing that dirty butt is kinda hilarious and gross at the same time," were just a few of the reactions.
Even better, shortly after the discussion blew up, a Japanese farmer named Renta (@taihibansei) chimed in – not to criticize, but to heap praise on the game's attention to detail.


"Honestly, cow butts really are that dirty. Especially when they're grazing, the whole herd often gets covered in mud," Renta tweeted. He explained that he majored in animal husbandry in college and is currently a rice farmer in Gifu Prefecture, giving him a deep understanding of cattle.
"The most amazing thing about this game is how incredibly realistic it renders the dirtiness of a cow's backside. This is a detail that could only be achieved by someone who truly loves cows," Renta added.
Renta even shared photos of real cows, explaining that farmers work hard every day to keep their cattle clean through regular brushing and maintaining their health. He noted that the in-game cow actually starts clean, only getting dirty when it drives through muddy sections of the track – a detail he praised as highly realistic.
The cow character first appeared in 1996's "Mario Kart 64" as a mere background animal on the tracks. This marks its debut as a playable racer. According to a previous official interview, Art Director Masaaki Ishikawa revealed that the inspiration came from a designer's sketch of a cow driving a car. "The moment I saw that drawing, I knew it had to be him!" Ishikawa exclaimed.