I want to become one with him, but I can't! -- On the night they celebrated three years since moving in together, 27-year-old office worker Kazuho had been hoping for a proposal from her boyfriend Wataru. And yet, he never raised the question of marriage... Since their relationship is sexless due to her own past trauma, she can hardly blame him. Just as she tells herself that the happy moments they spend together now are enough for her, she happens to meet a woman named Miya who has the same regional accent as Wataru. They hit it off, and Kazuho wants to introduce her new friend to Wataru, too, but for some reason he's acting strange... Ever since meeting Miya, something has gone off-kilter! Peaceful, everyday life breaks down in this story of romance and suspense.