To reunite with his mother after twenty years apart, Renji plans a hot spring trip. Reflecting on childhood memories with her brings him deep comfort. But upon finally meeting her again and feeling her warmth, long-dormant emotions begin to stir within him. When a letter arrives from his mother, the journey toward reunion begins in earnest. This meeting between mother and son is not merely a reconciliation after separation—it marks the beginning of a new relationship. As they spend time together on this trip, they gradually acknowledge their growing feelings, forming a profound bond while being swept into an overwhelming tide of emotion. Amid warmth and healing, a complex undercurrent of desire draws them closer, transforming their connection forever.