Jishou Kanojo no Kouhai ga Iiyottekuru.

This five-part one-shot delivers a compact dose of romantic comedy centered on a delightfully lopsided relationship. Its story follows an ordinary young man whose everyday life is turned upside down by a beautiful junior who has, entirely on her own authority, decided that he is her boyfriend. There was no confession and no mutual agreement—she has simply claimed him as her own, and she makes no effort whatsoever to hide it. What unfolds is a playful push-and-pull between the two. The girl flirts with her self-proclaimed boyfriend openly and without a trace of shame, her bold, teasing advances keeping him perpetually off balance. Because the relationship exists only in her declaration, every affectionate gesture carries an extra comedic charge: he never actually consented to any of this, yet her confidence makes it remarkably hard for him to deny her. Spanning five brief installments, the story captures the breezy charm of a one-sided romance in miniature. Each part offers another glimpse of the heroine's shameless affection and the flustered boy caught in her orbit, resulting in a light, sweet, and humorous portrait of a love that was declared rather than confessed.