A secret story of my abnormally loving relationship with my little sister. One day, unable to suppress my intense curiosity and affection for my sister An, I decide to sneak into her room. While the rest of the family is out, I open the door to find her masturbating while licking a recorder. Shocked and confused, I confront her—only for An to burst into tears from embarrassment. Flustered, I end up suggesting we enter a sexual relationship.