Ken unlatched the window, and sounds from outside flooded his ears with unprecedented clarity—the sheer volume and cacophony left him acutely uncomfortable, even inducing a bout of tinnitus. Not merely the sounds, but a barrage of intensely stimulating scents accompanied them, so overpowering they nearly brought tears and a runny nose. Hastily shutting the window, a frown creased his brow: this enhancement of his hearing and smell was perhaps excessive. If his senses were this acute at all times, would life in the city not become a torment?
Fortunately, his concern was short-lived. After forcing himself to acclimate for a while, Ken found the impact of his hyper-acute hearing and smell began to wane. Only when he directed his focus to his hearing or smell would the chaotic torrent of auditory and olfactory data reassert their clarity. Much like after his second blood ingestion, his hearing had already improved to some degree, but had he not one evening closed his eyes on the rooftop and suddenly perceived sounds he'd once deemed inaudible, he might never have noticed. The human brain filters and even blocks sensory information, retaining only what is desired or necessary.
In contrast to enhancements in strength, vision, and lung capacity—which were relatively straightforward to quantify—the improvements in hearing and smell were more elusive, requiring specialized equipment to record. In his room, with eyes closed, Ken endeavored to focus his entire attention on his hearing, absorbing the myriad sound signals. With his hearing greatly amplified, the sound information he received and his perception of time alike underwent a profound shift; it was not merely an amplification of all sounds, but a jumble of auditory data flooding his mind. Requiring him, in short order, to discern the source and nature of each sound, he was momentarily overwhelmed, as if his ears could not keep pace.
Uncertain how much time had passed, a wave of dizziness and nausea suddenly washed over him. He hastily opened his eyes, drew a deep breath, and diverted his focus. Could it be he still hadn't adapted to the enhancement of his hearing? Recalling the sensation moments prior, he soon realized it might not be his hearing per se, but rather that his brain was struggling to process the sheer volume of auditory input. The human brain, in truth, is perpetually inclined to take shortcuts—though such "laziness" is in fact a means of self-preservation. Sensory organs ceaselessly gather information, yet this data is always "selected" based on necessity. Often, what we see, hear, smell, and feel is far more abundant than we realize. Consider those optical illusion diagrams with blind spots: at first glance, people often miss peculiar details, only noticing them upon hint, when in fact they had been visible all along, merely overlooked by the brain. Now, though Ken's senses had evolved to receive information exponentially more, his brain's capacity to process it seemed not to have evolved commensurately—especially since his prior training had never involved absorbing such a deluge of simultaneous auditory data.
After resting a while, Ken shifted his approach, focusing solely on individual sounds.
Amidst the clamor of passing cars, vendors' cries, and distant music, Ken meticulously filtered and selected, pinpointing the sound closest to him… Drip, drip—the sound of a dripping faucet? No—not his own, but the neighbor's. A gurgle and rush echoed through the pipes: the upstairs neighbor flushing the toilet, wastewater draining away. A crisp gunshot? The young person upstairs playing a shooting game or watching a film? A faint murmur of speech, seemingly a woman's voice, but thin and buzzing, indistinct and unintelligible.
Ken exited his room, walking down the hallway with narrowed eyes, then descended the stairs in pursuit of the female voice's origin. This ability to pinpoint sound sources had been a focus of his training in recent days, and now it seemed to be yielding results. Minutes later, he traced the voice not to their building, but to the grocery store diagonally opposite—where the owner's daughter was on the phone. Ken now stood across the street, a dozen meters from the store; the daughter was on the second floor, out of sight and separated by a wall. Yet Ken could hear the content of her conversation. In that moment, the entire world seemed muted, save for the voice on the call. This required his utmost concentration; the moment he relaxed or diverted his focus—such as when the store owner greeted him—the daughter's voice grew faint and indistinct, as a cacophony of varied sounds from all directions immediately flooded his mind.
For now, though, Ken remained astounded by the extent of his enhanced hearing. This magnitude far exceeded his prior expectations. After all, when he had trained his physical strength before, post-ingestion enhancements had remained within normal human bounds—save for the abnormal speed of strength recovery and endurance, absolute strength had not surpassed what a typical person could achieve. Now, however, after merely five days of training, his hearing had far surpassed that of an ordinary person, and he doubted any amount of training could enable a normal person to reach such a level. Ken speculated, however, that the enhancement of his auditory and olfactory organs themselves might not be substantial, but rather that his innate sensory potential had not been fully realized.
Ken, still accompanied by the night, wandered as he had on previous evenings, testing his newly honed hearing and smell, refined through targeted training and mutation. If, when he first sensed the series of bodily mutations, he had felt fear and apprehension, now he was filled more with curiosity and exhilaration. Having discovered he was not immediately in mortal peril, despite the various inconveniences, the enhancements to his bodily functions from these mutations had led him to adopt a more proactive stance—since change was inevitable, why not guide it toward his desired ends?
In recent days, Ken had spent nearly every night wandering the streets, memorizing dozens of nearby alleys and roads. Yet tonight, walking them again felt entirely novel, much like the first time he ventured out late at night days ago.