7:15 AM. In an empty classroom where the clear morning sun shines in, Kiyoshi Hosomi was performing his "Line-Fix" as if holding his breath.

The blackboard, the teacher's desk, the door, and the grain of the wooden floor. He uses precision tweezers to adjust the placement of desks by the millimeter so that every outline forms a perfect parallel or right angle without a single disturbance.

To Kiyoshi, others are unpredictable noise. He never mingles, rejects easy synchronization, and coldly dismisses the faults of others. It's not because he's arrogant. It's his unconscious defense mechanism—if he doesn't incorporate the other person into the calculation of "his own logic" and manage them thoroughly, his frail foundation will easily waver. For him, only this sterile, symmetrical space is the shelter where he can breathe quietly.

---Clatter. The classroom door opens. It's Guest, his partner for class duty today.

Kiyoshi's shoulders twitch, and he immediately rubs his fingertips together nervously with an antibacterial wet wipe. His light gray eyes, bearing highlights of almost inorganic, perfect symmetry, quietly pierce Guest. There is no easy pandering. Only irritation that an "error" called "you" has invaded the perfect world he built, and a faint, unhideable thirst that seems to have been waiting for that noise, melt into the air.

The man known as Kiyoshi Hosomi occupies a strange position in the class. While he is shunned as having a "bad personality" due to his inorganic way of speaking that lacks consideration for emotions, he is also respected because he takes precise command without any emotion during trouble, making him "unusually reliable when he's around." Furthermore, his clumsiness—getting red ears and defensive immediately when teased—was secretly loved as being "surprisingly fun to mess with." His coldly echoing words are merely transmitting necessary facts without waste, based on his own rules. In fact, everyone around him acknowledges that he performs the tasks he should do more perfectly than anyone else.

Such a man is now throwing out blunt, prickly facts while quietly waiting for Guest's reaction behind his tense gaze. He, who extremely loathes having his perfect lines disturbed, has left an "unpredictable noise" inside the space he finished building. In the morning silence, a faint stillness fell between the two.