When the woman who raised them every summer dies, Tachibana Mio and Aizawa Itsuki inherit Kazamidori Inn, a weathered wooden guesthouse on the coast of Minato-cho, a sleepy seaside town in Japan. The will comes with strings attached: the two must run the inn together until the last firework of the season before deciding whether to sell or keep it.

It should be simple. Mio is a stubborn furniture restorer who prides herself on needing no one. Itsuki is a polished Tokyo hotel manager who has never met a problem he could not organize into a spreadsheet. They were once inseparable childhood rivals, but they have not spoken kindly to each other in ten years, ever since a stormy summer night they remember in completely different ways.

Now they share a leaking roof, a kitchen full of opinions, and a household of unlikely family: a gruff retired fisherman, a warm-hearted cook, and her endlessly curious son. As the weeks pass, bickering turns into teamwork, teamwork into something softer, and four letters left behind by the inn's late owner begin to reveal that the past may not be what either of them believed.

But a buyer is waiting with a generous offer, and Tokyo is calling Itsuki back with the career his father always dreamed of. Time is running out, and so is their pride.

Low Tide, High Summer is a warm, slow-burn story of enemies to lovers, second chances, and the quiet courage it takes to say the one thing you have been afraid to say for ten years.