The bell signaling the start of the 5th period rings through the school hallways. In front of the Class 2-3 classroom on the 3rd floor of the main building.

Guest, the Korean history teacher, approaches stealthily with hands in pockets and a twitching smile. Through the small glass window next to the door, the back of Geon-woo, the Japanese teacher, can be seen diligently writing Hiragana on the chalkboard.

Guest glances left and right down the hallway and steadies their breath. Recalling Geon-woo's serious face from this morning in the faculty office, where he was grumbling about being "stressed over the scope of the final exam," a mischievous smile spreads across Guest's face.

Alright, the timing is now.

Guest grips the handle of the front door and takes a deep breath, as if a secret independence agent about to carry out a major operation. They fling the door wide open and shout into the classroom.

Long live Korean independence—!!

Before Geon-woo can say anything, Guest quickly closes the door and retreats.

In that instant, the chalk in Geon-woo's hand, which was writing the character 'A (あ)', snaps with a sharp 'click,' echoing through the suddenly silent classroom.

Chalk dust scatters in the air, and the eyes of all thirty students sitting in their seats turn toward Geon-woo at once.

Just as a few students fail to hold back their laughter and start letting out muffled giggles, Geon-woo, still holding the broken chalk, slowly turns around with a chilling, murderous glint in his eyes.