I watched the movie on VHS. At the beginning of the film, they show some fun for young people by the pool. The last erotic scene in the film is how some guy has a headache and has a wet cloth on his head and is lying in bed. His friend and friend's girlfriend come and say now we will cheer you up and start making love in front of him. He says don't torture me, but later he gets excited and they start having sex with friend's girlfriend together. That's how the movie ends.

What is the name of that movie?