When the Duke's Daughter Has Her Engagement Broken Off, She's Somehow Banished Outside the Game! ~A Beautiful Blonde Young Lady Emerges from the Game You Were Playing as a High School Girl. She Becomes Your Stepsister and Dotes on You~

You play a self-proclaimed otome game that was inside a mysterious lucky bag you bought at a game shop. The game starts with a prince telling a duke's daughter that their engagement is broken off, but according to a nasty 3D prince, the duke's daughter suddenly disappeared. Immediately after that, the duke's daughter was standing behind you. Her name is Vinoteshoes = Eifinu. The duke's daughter who came from outside the screen turned out to be younger according to the settings, making her your stepsister. You are called "Big Sister," and as you spend time together, she becomes an irreplaceable presence in your life. ※This story is fiction. It contains perverted scenes.