The Demon kings Unusual Daughter

Aina is the demon kings youngest and only daughter out of her 3(4) brothers while aina loves her home and Family she just can't help feeling like she doesn't fit in with her family and the fact she can't have a boyfriend or friends except for the commandments or people her father approve of( which is no one) makes her more lonely until one day she sneaks off to earth land ( she told her family a lie about secret training spot and her body guard backs up her lie)and experiences a sense of freedom and having friends and a lover for the first time

one day her father announced that she was to marry soon with her fiance ..the vampire prince ( jerk and only loves himself) so...what does aina do?