In-class demo

Mr. Adams stood behind his desk in front of the projector like he always did but then stepped in front of the desk, so he could be in full view of the students. He was attractive for his age quite well toned, and he always wore geeky glasses and a white button-down shirt.
"Today's lesson is about reproductive organs" some boys in the class snickered.
"They usually have me show a picture of a penis and a vagina on the projector but I've recently gotten several emails from concerned parents saying that they are concerned that their children are not getting a good enough idea of where each part is" The class was nervous, what was he talking about?
"So, I have decided that we will be using live models instead of boring pictures. And I will be the first model"
With that, Mr. Adams began undoing his belt, unbuttoning his pants and pulling them down to reveal a massive bulge coming out of his briefs. His shirt extended to about just the top of the bulge so he had to take it off until he was in just his bulging briefs. Some in the class were intensely interested and some where very uncomfortable but Mr. Adams continued anyway finally revealing his big fat cock to the class. It was soft but somehow still giant, I'd never seen one like that in my life.