I believe this is the first release of Softporn Adventure. Written by Chuck Benton in 1981 Softporn Adventure was definitely one of Sierra's more risque titles and eventually inspired Al Lowe to create Leisure Suit Larry: In the Land of the Lounge Lizards.

Ahhh, the infamous cover of the Softporn folder.
Here are some interesting facts (Thank you John Williams):

• The hot tub was located at Ken and Roberta's house
• The circles in the background is an image of the top of the hot tub (just duplicated)
• The woman on the far right is of course Roberta Williams herself!
• The man was a waiter from a local restaurant
• The woman in the center is the wife of the creator of Ulysses and the Golden Fleece
• The woman on the left was a shipping clerk at On-Line Systems
• Yes, all the women are indeed very naked