I'm staying at my brother's house while focusing on my studies during my second year of ronin life. However, I can't help but be drawn to my sister-in-law, Haru. Without her around, I feel restless every day and can't concentrate on my studies. One day, I went to take a bath, only to find Haru had fainted from a long soak. I had to take care of her unconscious body. But for a virgin like me, Haru's figure was overwhelmingly stimulating, shaking my heart deeply. What will happen between us? An intensely thrilling development awaits.