You the protagonist are a 18 year old that is about to finish highschool. You live with your Mother, Father and a hot Sister (Mia)
The game starts 2 days before the last day of school. You are behind in school and need to catch up on studying to pass. Your parents are going on a business trip to France for a weak. You are studying till late, your sis comes home and she is drunk. You try to take advantage of that.