Nee-chan's Suggestion ~Big Sister's Mischievous Sex Life~

A visual novel set in a school and slice-of-life setting. The protagonist Natsuno Shinji attends school while helping his sister Ai run a coffee shop. His life takes a turn when he befriends Matsunaga Shigure, a popular schoolgirl. His sister Ai (an extreme brocon), childhood friend Kamiya Aoba, and his step-mother Utako all misunderstand Shigure to be his girlfriend and embark on a comedic battle for his attention, involving various playful and intimate schemes. The story escalates as Shigure and others join in the competition for the protagonist's affections.