Highschooler Ito (Shirasu Jin) is a serious, hard-working student aged 17 years. But he is also bored and feels unfulfilled.

On his way home from school, Ito often plays a sort of game, challenging himself to walk along a long white line in the road.

One day, while he is playing his lonely game, he comes across another high school student, the naïve but friendly Nishi (Raiku). Ito instantly falls for Nishi's uncomplicated charms.

The duo meets again, but they only ever seem to get to spend time together when they are returning home from school. In a fit of passion, Ito suddenly kisses Nishi – and is overjoyed to discover that Nishi also has feelings for him.

The tale follows the two boys as they transition out of late childhood, and into adulthood – and are forced to take on brand new challenges that test their love at every turn.

This drama was based on the hit manga title of the same name, which was released in 2017.