Die Rache der Ostfriesen (1974)

Scene starts with two slim blonde girls in their 20s sitting outside at a patio table, laughing, sunlight hitting their faces. One’s got short straight hair, the other wears it long — both in tight summer tops and jeans. A guy in his 30s joins them, gray at the temples, slim build, pulls one girl onto his lap and starts making out. They move off camera but return later with clothes adjusted, then go inside a kitchen where he’s jerking off while watching them kiss each other. The girls go at it with real tongue, one pushing the other’s face down into her crotch. Camera zooms in close when the guy fucks the shorter-haired blonde doggy style against the counter — she’s moaning into a dish towel. Second girl sucks his dick while filming on her phone, then rides him slow in front of the fridge. The final shot is all three half-dressed, passing around a drink like nothing happened.