Yuu's entire world collapses in one conversation, and the only solid ground he finds is a girl who turns out to be his stepsister. The movie doesn't wait to complicate things, it knows that's the only reason you're here. What makes this work is that it never pretends the situation is anything other than what it is: two kids caught in their parents' chaos, finding each other at the exact moment everything becomes impossible.
Yuu's world shifts the moment his parents drop their bombshell: they're divorcing each other to marry a couple they just met. It's chaotic, confusing, and Yuu needs air. During a walk to clear his head, he spots a girl that stops him cold. She's striking, effortless, and he can't look away. What starts as casual observation becomes something more deliberate as he finds reasons to follow her through the city, each glimpse deepening an attraction he can't quite name. For the first time since the announcement, Yuu feels something besides anger and dread. Then reality crashes back. The girl he's been quietly falling for turns out to be exactly who he shouldn't want: the daughter of the couple his parents are about to marry into. Suddenly, his feelings collide with impossible circumstances, and what felt like fate starts looking more like a cruel joke. The film captures that bittersweet moment when first love arrives dressed as a complication, setting the stage for everything that comes next.