Ms. Heather, her muscles bulging and glistening with power, took charge of the situation. "Justin, I think it's time we show Amanda just how potent your cum is." With a wicked smile, she grabbed him by the shoulder and spun him around so that his cock was right in front of Amanda's face. "On your knees, little one," she ordered, and Amanda couldn't resist the power in her voice. She sank to her knees, looking up at Justin's cock, which had grown to a massive size as well. It was thick and veiny, and it throbbed with power.
Ms. Heather looked down at her with a dominant gaze. "You want to grow, don't you?" she asked. Amanda nodded meekly. "Then you're going to have to suck him off. And you better make sure you swallow every last drop." Amanda opened her mouth and took him in as best as she could, her cheeks stretching around the girth of his shaft. It was like trying to swallow a watermelon, but she was determined.
Justin was a bit concerned at first, but as he saw how eager Amanda was, his nerves disappeared. He watched her struggle to accommodate his size, her eyes watering a bit as she gagged and coughed around his cock. But she was a quick learner, and soon she was bobbing her head up and down, taking more of him in with each stroke. His muscles tightened and his stomach clenched as he felt his orgasm approaching. He looked over at Ms. Heather, who had taken a seat on the desk, one hand playing with her own swollen clit as she watched the scene unfold. She nodded, giving him the go ahead. With a final grunt, Justin released his load into Amanda's mouth. She did her best to keep up, her cheeks bulging with his cum, but some dribbled down her chin.
Ms. Heather's eyes were glued to the scene, watching Amanda's throat work as she swallowed his cum. She could see the desire in Amanda's eyes, the need to grow. And as the last drop slid down her throat, Amanda began to feel the warmth spread through her body. Her muscles tensed and swelled, her clothes ripping away as she grew. Her breasts and ass grew rounder and firmer, her arms and legs bulged with newfound power. In moments, she matched Justin's size, standing tall at just over 7 feet.
The three of them looked at each other, panting and covered in sweat. The room was a wreck, but none of them cared. The power they now had was intoxicating. Ms. Heather slid off the desk, her muscles rippling with each movement. She looked at Justin and Amanda with a glint in her eye. "Now, let's see just how much you two can handle," she said with a smirk. "I want to see what you're really made of."