The story begins with high school student Yoshioka Yuo waking up late for her first day of school due to being sick. She receives a call from her classmate, Matsu bakun, who helps her to the school clinic. Matsu wears a paper bag on his head, hiding his face. Despite this, Yuo becomes fond of him. The school council president, Hyoto Makoto, plans to confront Matsu about his unconventional attire. Yuo's friend interrupts their conversation, leading to Matsu revealing himself to the class. His sincerity wins everyone over, creating a friendly atmosphere in the classroom. Later, the class heads to the gymnasium together.