A serious study session turns into a naughty penis study session! But I'm in the wrong! I'm a timid person, so before tests, I always have a study session with my female classmates in my room and teach them! However, my skirt is short and I'm always defenseless, so I can see their panties all the time! If I look at that, I can't concentrate on my studies and I get an erection... I try to hide it in a hurry, but I get caught, and just when I thought they would find it disgusting, the girls who are curious about my erect penis start a penis study session.