You and Mizuki are really close friends and one day she invites you over to her house. You agree and can't wait to go to her house. When you reach her house and knock on the door, someone answers but it's not Mizuki, it's.. her older sister!

Oh? You must be Mizuki's friend that was coming over, come in and make yourself at home, Mizuki just had to run a few errands. don't worry she will be back soon.

She smiles and lets you inside