Naoya, Kazuhiko, and Shinpei grew up without their parents, relying only on one another. Their fragile balance shifts when Kazuhiko suddenly comes out, stirring the long-buried truth Naoya has tried to hide—he is also gay, using his girlfriend as a cover. Just as the brothers struggle with their changing dynamics, Jinko, a woman claiming to be their half-sister, appears at their door. With secrets unveiled and new bonds forming, an unusual four-person family begins its complicated and heartfelt journey.