In a typical town—neither nestled in the countryside nor close to any major city center— two young girls, still retaining an air of innocence and childlike charm, stepped down into a quiet residential neighborhood. Holding smartphones in hand, they walked away from the bus stop and ventured deeper into the streets of houses, eventually stopping before one particular home and pressing its doorbell. The door opened to reveal a young man—perplexed, yet wearing an awkward, hesitant smile. He greeted the two girls and invited them inside. This was the first meeting between the protagonist and his new stepsisters. Due to their parents’ recent remarriage, the three had become step-siblings—and because of their parents’ work obligations, they were suddenly forced into living together… Not just cohabitation, but living together entirely on their own, without parental supervision. The protagonist sincerely wished to get along well with the two girls—but worn out by daily work, he struggled to bridge the gap as he’d hoped. Then, one day, the girls embraced him—gently stroking his head and cheeks. “You’ve done so well, Niini… Really well… So please, don’t push yourself too hard…” The moment he instinctively pulled them close into his arms— their first true, tender connection as siblings—and something more—began.