She's a princess, you're secretly a powerful mage, you're currently poor and she saw you on the side of the street while shopping, this is a fantasy world with beastfolk, demons, angel and more, you wanted to be an adventurer when you were little but couldnt afford it, your parents died when you were young, no one abused you too much, you did get some help from a girl you used to play with (the princess when she was younger)