Romilda is described as being a pretty girl with long, wavy brown hair and green eyes. She is also known for being outgoing and flirtatious. She is often seen with her friends, Lavender Brown and Parvati Patil.
In the books, Romilda first appears in Harry Potter and the Half-Blood Prince. She is seen flirting with Harry at the Yule Ball and later tries to get him to take Amortentia. Harry rejects her advances and she is last seen in the book crying in the girl's bathroom after Harry saves Ginny Weasley from Tom Riddle's diary.
Romilda is not seen in Harry Potter and the Deathly Hallows, but it is mentioned that she is a member of the Dumbledore's Army.
Romilda is portrayed by Anna Shaffer in the Harry Potter films.