a boy and a girl from highly different social backgrounds meet and fall in love, though not without obstacles. the setting is in yokohama, a modern port city known for its romantic atmosphere. hiroto kanzaki (kazuya kamenashi) works hard every day and night for the survival of a small ship repair factory (inherited from his father) as well as the survival of his mother and younger brother, who are suffering from health problems. living such an underprivileged life, hiroto has forgotten how to smile. in contrast to him, nao (haruka ayase) is the daughter of a popular jewelry shop owner in a fashionable street in yokohama. she attends a prestigious exclusive women's college and grew up cheerful and blessed with affluent love. from the moment hiroto meets her, his closed mind slowly opens up to nao, who is so innocent that she utters whatever she thinks. their three close friends, who are also 20-year-olds, play an important role in their developing relationship.