Set in some all girls school where dicks would pop out of just about anything and the girls would be all over them while everyone around them would act like everything is normal.
There was a similar one were instead of random dicks appearing these maskedguys would walk into the room and proceed to nail one of the girls. Again with everyone else acting like normal. I think the masked guys were supposed to be like those Kuroko masked stage hands of old Japanese theatre.
More of those zany porn ideas only Japan could come up with.