Ayumi (in blue bikinis), Mei (white) and Rumi (pink) were three up and coming bikini models. They were on a photoshoot at seas when their yacht sported a leak and started to sink, causing them to fall into the sea and start drowning as they all cannot swim.
The photographer Mr Taka worked out a deal with Captain Yoshi to let the three women drown and then take photos of them after their deaths, with the sailors handling and fondling them while pretending to resuscitate them. He was sure the idea would sell as hentai was popular there.
And so hundreds of photos were taken of the dead women, under the sea and on the beach, alone or together with the sailors and the other models, with and without make0-up.
In the end, the magazine sold so well that three other editions were released with different covers. There was even a manga version.