It is a misspelling. Mr. River means He xiansheng in Chinese, the Chinese word for "river!" has been combined with its English translation, and the "i" which should not be there is just a typo.

You could be well wide of the mark there, Turnoi. The 'i' may well have been put in by that troublesome bottle of baijiu the poster was drinking, but I think he meant Herr River- the big boss. But he has presented us with a mystery-so we should ask him.