Perhaps the cliff is a key element in the narrative structure of the buffalo story. It could be used to build suspense or add drama. For instance, Cheer could be on the cliff when something unexpected happened to the buffalo, like a stampede or an encounter with a predator. This would make the story more engaging for Norm. Also, the cliff might be a place that Cheer associates with a particular emotion related to the buffalo, such as awe or fear.
The cliff might be the setting where Cheer witnessed something related to the buffalo story. Maybe it was a special place where the buffalo were sighted or some event involving them took place.
The cliff could be a symbolic location in Cheer's buffalo story. It could represent a place of danger or a vantage point from which Cheer observed the buffalo. For example, if the buffalo were in a valley below the cliff, it would be a great place to watch their movements. Also, it might be a place that holds some personal significance for Cheer, like a place where he had an important realization about the buffalo.