Despair (1978)

A mature guy with short brown hair and wrinkles stands in a dim hallway, getting a handjob from a woman in a dark feather boa. She’s slim, brunette, early 20s, wearing heels and almost nothing else — you see her back and ass as she leans into him. Later, they’re at a dining table lit only by a lamp — she gives him a blowjob while glasses and an empty wine bottle sit nearby. He eats her out on the stairs afterward, her legs spread on each step, natural light from the window highlighting the shot. The camera uses strong side lighting in most scenes — shadows add mood, especially in the cluttered room with skulls and crosses. No quick cuts; the shots linger long enough to notice details like her nails on his shaft and how he grips the stair rail while going down on her.