Dear Mother, I hope you're doing well. It's been almost a week since I arrived at my older brother's place in Tokyo. Thanks to my brother and my sister-in-law Miki, my exam studies are going smoothly... But as I try to focus, my mind keeps drifting to Miki's body. The heat and my rising desires intertwine, leaving no trace of rational thought. Then one day, my heart begins to waver. My relationship with Miki grows increasingly intense, like a sultry summer night, gradually deepening beyond control. And this rising temperature is about to become the turning point that changes my life forever.