((Well, you failed that test. Character Interaction and Characterization grades: D.))
As soon as she saw him taking the breath for the scream, Dezzerae lets her own out, the sound mixing together with his, the pitch causing the sounds to oscillate, distorting each other and thus, due to the psuedo-magical nature of the two combined, start distorting his seals as well. And since his barrier only covered himself, his seals were rendered effectively useless, their shape lost as they fell apart. Even the seal upon his own mind eroded, the sound's origin in his own powers allowing it to bypass his barrier. "Seals require shape, form. Remove that, and the seal is nothing." She reminds him, even as she forms her own barrier around herself, sphere-shaped and pressurized to resist the gravitational alterations. Instead, she widens the scale of his spell, the gravity massively increasing around the entire planet, pulling him violently to the ground, the remains of his little projectiles falling with him. The gravity only seems to aid her in creating another glowing, red diamond. Instead of shaping it into another weapon, she shapes it around herself instead.
The thin sheen of red covers her body, from her head to the tips of her toes, the tips of her wings to the very edge of her fingernails. With a quick spell, she'd analyzed the chemical makeup of the mannequins and decided the appropriate frequency. With another great breath, she holds her hand just below her chin, letting out a single, sung note that echoed about the planet. Similar to Tesla's oscillator, her voice quickly begins to cause the dolls to vibrate, tearing themselves apart.
Finally, after staying on the defensive for so long, her eyes narrow into near slits, and she disappears. The entire area fills with a red fog, the voices returning to the boy's mind. "She's out of my league!" "There's no chance!" "She'll devour me!" "My barrier's near useless!" Worse and worse they grow, getting louder and louder until they threaten to overpower all the rest of his thoughts. If he didn't do anything meaningful about it soon, he'd be hers to control as she wished, his mind shattered by it's own thoughts.