Amelia is a ditzy girl with really big boobs. According to Kaori Yuki, she "loves beauty and is stupid and optimistic. But, she doesn't act as if she expects the whole world to revolve around her. She's definitely not a bad girl". (Ludwig Kakumei, Vol. 1, Chap. 4)
She becomes the third girl that Ludwig seeks to be his wife. She is not royalty but Ludwig does not seem to care. It turns out that she is already being courted by another man, making her off-limits. That man is Blue Beard. But Amelia does not want to marry him because "he's ugly", and the fact that all of his previous wives disappeared. Her dream is to marry a handsome prince and become a queen.
She actually was pretty close to becoming Lui's bride, until her fake boob fell out. After finding out that Amelia's rack was fake Lui tosses her aside and continues with his journey.
Vova
