In the setting of Girl Factory or something similar, many girls are raised in institutions.

About twenty of them go on a trip to the beach along with their shared legal guardian. They play around topless for a while, but it turns out than not too far from there, a sort of game show is airing live:

A guillotine attached to a randomization mechanism like a Wheel of Fortune has been set up, and people are invited to lie into it and give the wheel a spin. In most cases, the participant will win a prize, but there is also a chance that the blade will drop instead.

First, only a few people participate, as usual. But, whether by their own volition or with encouragement, the girls agree to go for it together. As they are minors, their guardian needs to give permission. One by one, and while showing various different attitudes, each of them is put in the guillotine, and not all of them get off of it in one piece.