This is how Wikipedia explains the river spirit:
- River Spirit (川の神, kawa no kami)
- A customer of the bathhouse originally thought to be a "stink spirit" who is assigned to Chihiro and Lin. Yubaba suspects that he may be something more than a stink spirit; when Chihiro helps him by pulling trash that had been dumped into his river out of his side (Miyazaki had a strong interest in the environments and wished to portray the destruction of rivers), her suspicions are proven correct. He is in fact a famous and wealthy river god. As a reward for cleaning him, he gives Chihiro a ball of plant material which, viewers are told by Kamajii in the English-subtitled version, is a "healing cake". In the English dubbed version, Kamajii simply states that it is medicine from the river god. The "healing cake" is later used to heal an injured Haku through ingestion and to cause No Face to vomit the people and vast amounts of food he ate during his rampage. It is implied that the taste of it is extremely bitter, as demonstrated when Chihiro tries a bite and reacts violently.