In Japanese schools, the "kumi" (homeroom) and "bukatsu" (extracurricular clubs) are the centers of social life. Students spend most of their day with the same group of peers, leading to deep, long-lasting bonds. Clubs, in particular, foster a sense of "senpai" (senior) and "kohai" (junior) hierarchy. This vertical relationship is a cornerstone of Japanese social interaction, teaching students about respect, mentorship, and the collective effort required to reach a goal, such as winning a prefectural sports tournament or performing at a culture festival. Romantic Storylines: From "Kokuhaku" to Graduation