Grass-mud Horse

Over a million people have watched a video of children's song about a courageous alpaca-like creature called the Grass-mud house who fights against river crabs in the Chinese desert. 
From Slate's Explainer:

"A mythical beast known as the "grass-mud horse" has become an
Internet phenomenon in China. The New York Times reported Thursday
that the alpacalike creature's Mandarin name just happens to be a very,
very dirty pun. Times style rules prevent the paper from clarifying the joke,
but other, less-dignified outlets explain that the phrase Cao ni ma is a
homonym for "fuck your mother" in Chinese. Is some variant of motherfucker
used all over the world?"

A collection of YouTube videos to further your research in this delicate matter.