The boy with the big potato and two naughty female students

A serious study session turns into a mischievous one. But I'm really bad at this. Before exams, I always have a study session with the girls in my class in my room and I always teach them. However, because of my very short skirt which I always cover up, it looks like panchira. Seeing that, I can't concentrate on studying and I get aroused. I hurriedly try to hide it, but thinking back on it makes me uncomfortable as a study session for curious girls about arousal begins.