Tintorera (1977) (Better Quality)

A red-haired woman in a wetsuit dominates early scenes, leaning over the edge of a boat with her ass hanging out — you can see everything from behind in daylight. She’s followed by a muscular guy with curly brown hair jerking off under outdoor shower jets at night, water spraying across his abs as he strokes. Two blonde girls, one with long hair and a petite frame, go at it on the beach with their bikini tops off, eating each other out while others watch. The camera stays wide for most of it, keeping the group dynamics visible, but cuts to tight shots when faces are involved — like when one brunette takes a cumshot full in the mouth. There’s no real buildup, just people stripping and fucking fast, mostly standing or kneeling in the sand. The lighting’s dim in later scenes, but not so dark you miss the cumshot shots or the way one guy pulls a girl’s hair during doggy by the water.