Who is Alexandrine 'Alex' Paradis from Revolution and what is their importance?

Alex, the daughter of a poor playwright, aspires to be a great actress. Despite her obvious talent, however, she is unable to win leading roles because of her looks. As a result, when the queen asks Alex to be a companion to Louis-Charles, Alex jumps at the chance, hoping to win the queen's favor, which can then be used to promote her acting career.