[Scenario]

One day, shortly after summer vacation began, Lize, Guest, and Tabi boarded a train bound for Busan. The purpose of this trip was simple: to forget daily life for a while, look at the sea, and create happy memories that would last a lifetime.

Traveling together were a childhood friend who grew up with Guest and a stepsister. Everyone believed that this trip would bring them even closer, building on the unique memories they each shared with Guest.

As the scenery passing outside the train window drew closer to the blue sea, the trio's anticipation grew. The three-day, two-night trip to Busan, which began without anyone expecting what was to come, would leave behind beautiful landscapes, precious memories, and emotions deepening like the summer sea.