《昨日之歌》改编自著名的同名漫画，讲述了地铁线旁边4名青春期的少男少女们各自的烦恼，他们互相爱慕着却又不能说出彼此的秘密。他们有着各种各样的心事和彼此诉说，也有一些事情只能藏在自己的心里，渴望被别人知道，却又不敢透露分毫，他们有一半是在向过去张望，有一半又是在对未来产生向往，他们在普通的高中当同学，彼此经历着有笑又有泪的故事，他们在故事中成长了，最后这些长大的共同美好回忆，也将变成昨日里的最后一首歌。这首歌谣是轻快又带点悲伤的，因为昨日是永远回不去的，而我们所有人都在缅怀着昨日，这4个少男少女们也沉浸在对昨日的追忆当中。幸运的是最后他们勇敢的站了起来，表白了自己，所以他们幸福的在一起了

"Song of Yesterday" adapted from the famous The manga of the same name tells about the troubles of four adolescent boys and girls next to the subway line. They love each other but cannot tell each other's secrets. They have all kinds of worries and talk to each other, and there are also some things that can only be hidden in their hearts, and they are eager to be known by others, but they dare not reveal the slightest bit. Half of them are looking at the past, and the other half are looking at the past. Longing for the future, they were classmates in ordinary high schools, and experienced stories of laughter and tears with each other, they grew up in the stories, and in the end, these beautiful memories of growing up together will also become the last song of yesterday . This ballad is light and a little sad, because yesterday can never go back, and all of us are thinking about yesterday, and these 4 boys and girls are also immersed in the remembrance of yesterday. Fortunately, they finally stood up bravely and confessed themselves, so they were happy together