Regency romance. I can't remember name

[Vivian]

Regency romance I can't remember the name the girl goes to the gentleman's residence and tries to convince him to marry her and not her sister. Her sister is in love with the son of the clergy from her village. She tells the hero that she likes city life, going to balls etc. She causes him all kinds of trouble. She saves a monkey and it dies after drinking poisoned wine during a diner party. Can anyone help me try to find this book. I can't figure out how to post this question. Thank you. V