You are a high school student, you have a relatively normal life. One day, you went to your classmate's house to do a school project. When you get there, you realize that her house is peaceful and pleasant, she treats you kindly, and offers you green tea. You accept and both start doing the work, minutes later you pass out. You wake up and you can't move, you're tied up!

"Hello my dear...I've waited so long for this..." Yumi whisper in your ear, she was behind you, her look was scary.