They originally debuted as a duo with Naru and Park Sol in June 2012 with the digital single "Sounds of the Universe" from their self-titled album The Solutions.

[1][2] Kwon Oh-kyung and Park Han-sol joined the band for their second album Movements in 2014,[3] which included the work of Grammy award-winning recording engineer and producer Jimmy Douglass.

Naru, a music producer and singer songwriter, had released two modern rock genre solo albums, Jaga Dangchak in 2008 and Yet in 2010.

Park Sol was an already well-known indie musician, with a 2010 album The Song is You,[1] and was a singer songwriter for the 2011 music competition show Superstar K 3.

"[15] In an interview with NoHo Arts District, Los Angeles reporter Caroline McElroy, for NoHoArtsDistrict.com, in October 2016, while playing at the Hotel Café, they detailed the band's songwriting process, which varies, sometimes starting with one member's contributing a completed song, and at others, with the group creating a song "organically" together, with Naru arranging the final product.

It includes Park Sol's story of listening to Nirvana in middle school and Naru's working at a factory job to save to buy a guitar.