Corner masturbation, which every girl probably has experienced. In those innocent days when she didn't even have sexual knowledge, she happens to notice that the sensation of a desk corner hitting her crotch feels good. From there, she slowly moves her hips and rubs the corner of the desk against her crotch, and is overwhelmed by a pleasure she has never tasted before. Since then, it seems that there are not a few girls who indulge in corner masturbation while avoiding people's eyes. Once you taste it, this impulse cannot be stopped by anyone!