Gf sister (Romantically Yours). Romantically Yours

Mark's heart raced as he leaned against the cool tile of the shower wall, the steam enveloping him like a thick fog. The water cascaded down his chiseled chest, tracing the contours of his defined abs, as he tried to shake the tension from his body. He was a man of appetite, a dominant force in every aspect of his life, yet when it came to sex, he was still an uncharted territory, a dormant volcano waiting to erupt.  Mia, his childhood sweetheart, was a vision of curves and softness.
Her big ass and breasts were the stuff of his most vivid fantasies, and yet, despite her willingness, he hadn't taken their physical relationship to the ultimate level. He was waiting for that perfect moment, that perfect surrender. But the wait was becoming unbearable, his hunger for her growing with each passing day. Mia, on the other hand, was a giver. She'd drop to her knees without hesitation, her warm mouth enveloping his thing with a skill that belied her innocence.
She'd look up at him with those doe eyes, her hand stroking him with a rhythm that could drive a man to madness. And when she'd press her average yet supple tits around his shaft, the world would blur at the edges, leaving only the sensation of her body against his. But it was Kate, Mia's elder sister, who haunted his thoughts with a persistent, forbidden allure. Kate was a whirlwind of sensuality, her wardrobe a deliberate tease of short skirts and low-cut tops that showcased her voluptuous figure.
She moved with a confidence that Mark found intoxicating, and he knew that if he ever found himself alone with her, his control would snap like a twig underfoot.