Suddenly, my little sister came crashing into my one-room apartment where I lived alone. It was impossible to live together in such a tight space! Just moving around caused her breasts to brush against me, and I could easily see her changing clothes. Her big tits had incredibly pink areolas, and I started wondering if something was wrong with me. Of course, there was only one futon, so we had no choice but to sleep side by side. Her breasts glistened with sweat, and I couldn't take it anymore. I just wanted to touch them a little... I just wanted to squeeze them a little... But as I hesitated, wondering whether to stop, the supposedly sleeping Yuri whispered, "It's okay, touch me." I couldn't hold back any longer...