Second-year high school student Aoi Aioi is an aspiring musician Aoi Aioi. Her older sister Akane's ex-boyfriend Shinnosuke Kanomura is a struggling guitarist. Aoi and Akane's parents passed away in an accident 13 years ago, and Akane gave up her ambition of going to Tokyo with Shinnosuke to take care of Aoi. Since then, Aoi has felt indebted to her older sister. One day, she is invited to perform at a music festival as a session musician by a famous en singer named Dankichi. At the same time, Shinnosuke returns to Aoi and Akane's town after a long time away. Then, Shinno mysteriously appears- who is actually Shinnosuke from 13 years ago after traveling from the past to the present-and Aoi falls in love for the first time. 很不错。井の中の蛙 大海を知らず されど、空の青さを知る。期待！。冈妈·青春·天空之蓝。 茜（吉冈里帆 配音）和葵（若山诗音 配音）在很早之前失去了父母沦为孤儿，为了照顾妹妹，茜放弃了和当时的恋人金室慎之介（吉沢亮 配音）前往东京的计划，留在家乡找了份工作，扮演起了母亲的替代角色。一晃眼就是13年过去。 如今，葵出落成为了大姑娘，身为一名高二学生，葵并没有将心思放在考试和升学上，每天都漫无目的的弹着贝斯，毫无干劲。茜将这一切看在眼里，感到非常的着急。某日，镇上举办了音乐会，在现场，葵意外的发现了金室慎之介的身影，他回到了这个小镇上！与此同时，13年前年仅18岁的慎之介亦穿越来到了姐妹两人的身边。
