How does Florent meet La Belle Normande and what does she do that upsets him?

Muche, La Belle Normande's son, takes a liking to Florent and Florent discovers a soft spot for the child. La Belle Normande permits Florent to tutor her son, Muche, twice a week at her home. La Belle Normande becomes very flirtatious with Florent, which upsets Florent greatly as he is inexperienced with women and is extremely shy.