The piano pop ballad is written in the key of G major in cut time with a tempo of 62 beats per minute.

[4] In November 2014, she posted a Vine of her singing a line that she had made up, which was inspired by the television series Once Upon a Time.

Taking note of its popularity and with encouragement from her followers,[6] she adapted it into a full song titled "Lost Boy", which she posted on YouTube on January 18, 2015 and was released on iTunes on February 12, 2015.

[7][8] Dozens of Vine and YouTube users posted covers, which helped further its popularity and increased Berhe's following on social media.

[11] Mike Wass of Idolator called it a "pretty ballad" and went on to say that "[Lost Boy] is nostalgic, more than a little bittersweet and aptly showcases Ruth's smooth vocals.