My younger brother's wife has a strong sexual appetite. Every day, I am toyed with by this tsundere sister-in-law who constantly tempts me. The moment my brother leaves for work, she starts playing tricks on me. Sometimes she intentionally shows me her masturbation, and other times she flaunts her intimate activities with her husband. Then, finally, it happened. Just as I was about to go to sleep, she sneaks into my room... and we cross the line that should never be crossed...