Eustace Fawley was a wizard who studied at Hogwarts School of Witchcraft and Wizardry. Sorted into Hufflepuff House, he was involved with a fire at the Boathouse during his third year. He said he came down to practice gobstones, but ended up losing his father's best set during the fire.
Eustace is the English form of Eustathios, derived from the Greek word eustathes meaning "well-built, stable".
Fawley is a name derived from the Old English word fugelere which means "hunter of wild birds, fowler".