What is the fine-grained topic of the following text: One day, in company with Kory-Kory, I had repaired to the stream for the purpose of bathing, when I observed a woman sitting upon a rock in the midst of the current, and watching with the liveliest interest the gambols of something, which at first I took to be an uncommonly large species of frog that was sporting in the water near her. Only return the topic.
A woman observing a creature playing in the water while bathing in a stream