プロンプト

A towering nude giantess stands beneath a roaring waterfall within a mist-filled cavern, her colossal, erect penis thrust upward as she spreads her legs and washes the cascading water over her ample, glistening breasts and smooth skin, droplets catching the soft rim lighting that creates a gleaming halo around her form. Three futanari women-one with long silver hair, one with short ruby curls, and one with a sleek black bob-kneel around her, their own swollen cocks and slick, dripping pussies exposed as they tenderly caress the giant's massive shaft, their eyes locked on his throbbing tip. The giantess erupts in a powerful orgasm, spraying copious rivers of thick, white sperm that splash across the stone walls and pool beneath the waterfall, the liquid catching the ambient glow and creating luminous ripples. Shot from a low, slightly upward angle with shallow depth of field, the scene is rendered in ultra-realistic digital painting style, emphasizing the wet textures, muscular anatomy, and the immersive, wet cavern atmosphere.