My sister-in-law looked gentle and had a calm, kind personality, yet she had large, incredibly attractive breasts. I looked forward to seeing her so much that despite preparing for exams, I deeply desired to get closer to her. However, fearing my brother's anger if he found out, I remained tormented by guilt and anxiety, resorting only to masturbation. As I spent one summer living at my brother's house, these feelings grew increasingly intense. This story leaves readers wondering how my relationship with her will develop—and just how close I'll ultimately get to her.