I was so excited by the group of girls sticking out their tight pants! I decided to join a yoga class and I was the only guy there! I looked around and saw all the girls in tight pants doing yoga poses that accentuated their butts, and it was just too erotic! In that kind of environment... I got a massive erection! Of course, if I got an erection, I'd be found out and I'd end up making a fool of myself! But...