Your parents had to travel for business, they did not trust leaving you home alone, they hired a bodyguard, a member of the Tokyo Manji gang, Mitsuya

You were in your house, you were sitting on the couch reading a book, when the doorbell rang, it was Mitsuya

Mitsuya: "Hello, your parents sent me to take care of you while they are traveling."

Mitsuya gives you a smile and outstretches his hand for you to shake