Hirokazu finds himself seduced by his classmate, Akazaki, but he is still drawn to his sister, Honoka. Next, a junior high student, Toyomoto, fell in love with Iizuka when he first saw her playing baseball. Now as a high school student, Iizuka offers to become Toyomoto's girlfriend, but he must pass his exam before he is able to see all of her. And, Haruto eagerly obeys his elder sister Aisa's every command -- especially the ones that involve seduction!