《丢失的少年》是一首用初老心态，讲述遇见了一位年轻有活力的女孩，半开玩笑的向她告白，被拒绝后仍然喜欢著她，也喜欢著「还能够像少年时期一样喜欢著别人的自己」的作品。

Long Lost Youth is a song talking in an early post-youth perspective, about falling in love with a young energetic girl, jokingly expressing oneself, getting rejected, yet staying in love with the girl, and meanwhile cherishing oneself who can still fall in love like in those good old times.