Well, this a manga and most times things you see happen, could not happen in real life. There is not a good chance that NOBODY walked past the room and that there are no cameras in that room. If you don't like unrealistic yaoi, don't read hentai yaois.
@ Narci Cyst
I've had to explain his hundreds of times. It's yaoi, not biology 101. You don't read yaoi for the "real" life logic or science. It's called-say it with me-FANTASY. Fiction/fantasy. Just have fun and read it.
Wow dude you kind of just ruined the logic of the story lol
I agree with you ksb1978 nut there are limits he can't be that hudge ok it's hentai but this... and their face brr scary
I love good yaoi, but please, lets think about the science here: a mans penis is engorged by blood flow. That means that during erection, a substantial portion of blood is not being transferred to the brain (or other bodily faculties). That, in turn, means Sensei would not be able to wield that erection while still maintaing bodily function. He would simply pass out. And the student would be unable to facilitate the penis.
I dislike this based on the simple science.