It was the last week of April, a time when the cherry blossom petals had already faded to brown and were piling up over the drains.

Monday morning, around 8:40 AM, in the middle of the school arrival hour.

The footsteps of students passing through the school gates were either sluggish or noisy, or both. Some walked with their heads down and earphones plugged in, while others crowded toward the entrance, laughing and grabbing their friends' shoulders.

Spring sunlight poured diagonally through the hallway windows, but despite that warmth, there was something strangely sharp mixed into the air of Mori High School.

Old graffiti caught between wall tiles, empty soda cans left on windowsills, and the way the students passing in the hallway scanned each other with their eyes.

One could feel it through their skin just by stepping inside the building: the order here was maintained by something other than school rules.

The 2nd year Class B classroom was located second from the left in the 3rd-floor hallway.

The plastic '2-B' sign above the front door had a broken corner, and the door itself bore scribbles of unknown meaning scrawled in ballpoint pen.

Inside the classroom, several voices were already mixed together. Rough laughter and the sound of desks being tapped came from the back, while the chime of smartphone notifications rang from the window side. Standing at the door, all of it rushed at you at once.

In the back area of the classroom, Yamamoto Kenta was sitting with his chair tilted back.

His dyed red hair shone annoyingly in the morning sun, and his shirt was unbuttoned from the third button down.

Beside him, Kurogawa Ryuji sat with his arms crossed and eyes closed, leaning back in his chair in a posture that made it hard to tell if he was asleep or awake.

When Kobayashi Daichi tapped Kenta on the shoulder and whispered something, Kenta gave a smirk, and Kaito followed suit as if the laughter were spreading. Their presence alone created an unspoken atmosphere in the back half of the classroom.

8:55 AM. The front door of the classroom opened, and the homeroom teacher, Sato Akira, walked in with the attendance book tucked under his arm.

"A transfer student arrived today. It's a bit unusual since April is almost over, but..."

At those words, in the back of the classroom, Kenta remained tilted back in his chair with his arms crossed.

"Hah? Something interesting showed up. Don't you think, Kenta?"

Daichi's mischievous voice rang out with unusual clarity amidst the noise.

"Oi, is it a girl? A boy? Which one is it?"

Kenta's voice burst out unreservedly from the back. Ryuji didn't open his eyes, but the corners of his mouth twitched upward slightly.