The crimson hall had settled into a deceptive calm. The echoes of Sarah's last triumph still reverberated in her chest, each heartbeat synchronizing with the Lust Engine that now pulsed like a living entity beneath her skin. The pillars glimmered faintly, the energy from her previous exertions lingering in their surfaces. Sarah could feel it — the resonance of her own growing power, intertwined with the subtle warmth that had flowed from Rias, Koneko, and Rossweisse.
Akeno stepped forward, her gaze sharp, yet imbued with a quiet expectation. "Your Charm Domain was impressive," she murmured, voice almost a caress against Sarah's awareness. "But now you must learn the rhythm between souls. Heart Synchrony is not mere energy — it is the flow of emotion, desire, and intent, channeled as one."
From the shadows, Rias moved closer, her posture deliberate, a mixture of command and curiosity in her eyes. Sarah felt the first quiver of connection as their gazes locked — a subtle tug in the chest, an almost imperceptible tightening of the Lust Engine. Her pulse spiked, and with it, a flicker of heat spread along her arms.
Akeno's voice drew her attention. "Approach her. Let your energy respond naturally. Every brush of contact, every glance… can awaken power."
Sarah hesitated for only a moment before stepping forward. As she passed Rias, her arm lightly brushed against hers — a soft, unplanned frôlement along the elbow that sent an immediate ripple through her own body. The warmth was magnetic, and almost instinctively, the Lust Engine responded, sending a subtle pulse of crimson energy along her veins. The air itself seemed to shiver at the gentle contact, the hall amplifying the resonance.
Sarah PV: 110 / Lv: 9 / Force: 24 / Desire: 130 / Intelligence: 17 / Agility: 16
Rias's eyes softened, a faint recognition of the connection flickering between them. The tension that had been purely combat-honed now carried a different weight — the delicate pulse of trust, awareness, and mutual focus. Sarah felt her Heart Synchrony begin to stir, the first real signs of fusion with another soul.
Akeno circled them, observing the subtle reactions. "Yes… that's it. Let the energy rise. Feel it through every nerve, every glance. Sometimes, it's a light touch, sometimes a breath, but it always flows."
Encouraged, Sarah reached for the final step — her fingertips barely brushing Rias's. Their hands met in a fleeting effleurement, a momentary spark that seemed to ignite the very air between them. Rias's gaze met hers, unwavering, and for a heartbeat, the hall faded into a blurred haze of crimson and gold. The energy flared in response to the combined awareness, spreading outward in ripples that washed over the surrounding allies. Koneko and Rossweisse instinctively stiffened, feeling the surge of synchronized energy, yet they did not resist; they became part of the resonance, their own pulses contributing to the rising tide.
The shadows lurking at the edges of the hall, remnants of the previous trials, surged forward again, but their attacks faltered. The aura of shared intent and synchronized heartbeat twisted the battlefield, bending perception and energy alike. Sarah moved instinctively, weaving arcs of crimson energy that flowed through her limbs, guided as much by emotion as by conscious control.
Skill Unlocked: Heart Synchrony (Level 1)
Effect: Merge energy and intent with a partner to amplify both defensive and offensive capabilities. Emotional connection boosts power.
Sarah PV: 115 / Lv: 10 / Force: 26 / Desire: 150 / Intelligence: 18 / Agility: 17
The hall trembled with the unified resonance. The first successful synchronization pulsed outward, a visible wave that wrapped around every observer. Sarah felt a heady mix of exhilaration and vulnerability — the awareness of her partner, of the energy they shared, and of the immense potential still untapped.
Rias stepped back slightly, a subtle smile curling at her lips. "You've begun to understand," she said softly. "The flow is alive… it responds to intent, emotion, and attention. Every brush of contact is a thread, every gaze a current."
Sarah's fingers lingered for a heartbeat longer, the warmth between them intensifying as the Lust Engine adjusted, integrating the surge of shared energy. A gentle pressure against her waist — a supportive brush from Koneko moving past — sent another pulse of magic spiraling outward. Each movement, each interaction, each deliberate glance acted as a catalyst, expanding the synchrony.
The shadows, now fragmented by the sheer resonance of Heart Synchrony, attempted to regroup, but Sarah's control had sharpened. She directed the energy outward in graceful, precise arcs, the crimson light bending to her will, wrapping the echoes of her enemies in a tangible, almost tactile flow of power.
Sarah PV: 120 / Lv: 11 / Force: 28 / Desire: 165 / Intelligence: 18 / Agility: 18
Akeno's eyes gleamed with satisfaction. "This is only the beginning," she said. "Heart Synchrony is more than energy. It is trust, anticipation, and the courage to share the moment. You have felt the pulse — now you must guide it without faltering."
Sarah exhaled slowly, the hall calming as the waves of energy settled into a gentle hum. The initial spark of fusion had been achieved; the Heart Synchrony manifested as a faint halo of interlacing light connecting her and Rias, with subtle ripples touching Koneko and Rossweisse. It was incomplete, but unmistakably powerful — a tangible symbol of her growth, her bonds, and the potential of the Lust Engine fully awakened.
Akeno's voice cut through the quiet, sharp and approving. "Remember this feeling. Every bond, every touch, every glance matters. Let it guide you, but do not depend on it blindly. True mastery comes from understanding your own heart as much as the currents you touch."
Sarah's gaze lingered on Rias for a moment longer, noting the steadying warmth, the strength beneath her expression, and the unspoken promise of shared power. Her own heartbeat had slowed, but the pulse of desire — the driving energy of the Lust Engine — remained vivid, a constant reminder of the path ahead.
The hall began to fade as the Mirror Sanctuary dissolved into the lingering crimson light, leaving Sarah with the undeniable certainty that every bond, every connection, and every carefully measured touch could now shape her destiny. She had taken her first step into the deeper mastery of Desire, and the potential of the Heart Synchrony promised both power and peril in equal measure.
Sarah PV: 125 / Lv: 12 / Force: 30 / Desire: 180 / Intelligence: 19 / Agility: 18