My sister's Midori-kun

Sui has never quite managed to get along with Midori-kun, the college student who happens to be dating her older sister. With a seven-year age gap between them, he constantly treats her like a child and delights in teasing her at every opportunity. For Sui, his patronizing attitude is nothing short of infuriating, leaving her convinced that she will never see him as anything more than an annoying presence in her life. However, their dynamic begins to shift when Midori-kun takes on the role of her academic tutor. Forced to spend focused time together outside of casual family interactions, Sui starts to notice subtle changes in his behavior. Beneath the playful provocation lies an unexpected side of him that gradually comes to light during their study sessions. As this unfamiliar gentleness surfaces, Sui finds her frustration giving way to something far more complicated. What began as mere annoyance slowly transforms into the tender, bittersweet stirrings of a first love she never saw coming, leaving her to navigate confusing new emotions toward the one person she thought she could never stand.