Squeeze

Rachel looked into Paul's eyes then dropped her gaze back to his groin. With one small hand she grabbed his bag, encircling it with her fingers. She pulled his balls to the bottom of the bag, using enough pressure that both testicles were clearly visible through the stretched skin of his scrotum, then curled her thin fingers around the trapped nutmeat and used her free hand to cover the bottom part of Paul's testicles. Without looking up she squeezed both hands at once with all the strength her little hands could muster. His balls squished out between her fingers like small bits of a water balloon on the verge of bursting. The strength of Rachel's grip shaded her fingers with an increasingly whitening tone, in remarkable contrast with Paul's rapidly darkening red orbs.

Paul exhaled all of the air he had sucked in in an instant. No sound came out, but his mouth and eyes stretched wide open in a shocked expression, much to the enjoyment of his young female tormentor, who giggled with delight at his ridiculous appearance.

Laura, still holding the briefs cylinder at the ready, quickly reacted and **** them into his mouth deep enough to cause Paul to gag.

Rachel casually rolled her hands left and right, examining bits of the trapped boy flesh from different angles, maintaining pressure and balancing her wide squat stance on the stool, restraining Paul's frantically kicking legs. Her sister maintained her leg lock on his upper body, easily swatting away occasional approaches of his desperately flailing arms.
Paul was ready to scream, but only muffled cries came out through his make-shift gag as he was **** to inhale much needed oxygen through his nose.
The feeling of excitement of peeking at Rachel's visible pussy lip was replaced with a sensation of pure, overpowering pain, as his boner rapidly deflated to it's limp form for the first time since he left the apartment.

Rachel, who still giggled uncontrollably at the boy's animated reaction, felt her hands begin to tingle with soreness.
She took a moment to catch her breath, releasing the pressure but maintaining the ring around Paul's trapped boy parts, then looked up at Laura for further instructions.