My sister asked me to take care of my niece, who is about to enter a university in Tokyo, for a few days. When I met my niece for the first time in several years, she had grown into a neat and tidy, beautiful girl. The moment we were alone, my niece purposely teased me by showing me her pale, big ass in her panties. I tried to calm Kokoro down by telling myself, "No... it's my niece... she's my niece after all," but my penis was uncontrollable and I got a regretful erection. My weakness of having an erection was discovered, and she played with my penis and milked it with her vagina many times...