My nieces came to visit my parents' house and looked cute in their uniforms, which made my heart race... They had their bare legs exposed and immediately came into the kotatsu because it was cold, so when I looked inside, I found myself in a paradise of panty shots of my nieces' cotton panties! Maybe because their guard was down in the kotatsu, I could see their pussy lines clearly, and I got a boner. Then my niece found out that I was peeking and that I had an erection, and I was in a real pinch...! But then my niece was so curious that she started touching my erect cock, and even begged me for some sex!