Base (EP)

Jonghyun collaborated with various artists for his album, such as Younha, Wheesung, Zion.T and Iron.[3][4] His title song, featuring Iron as the rapper, is called "Crazy (Guilty Pleasure)" and was released digitally on domestic music sites on January 12, 2015, together with the album.[3] He performed in a showcase to introduce the album at the SMTown Coex Artium on January 8, 2015.[3][5] He told the media before his live showcase at the SMTOWN Coex Atrium:

To be honest, I am not confident in singing ballad songs. Fans have loved my ballads in the past, but I am not really good at singing them. For this album, I focused on introducing my style of music and what I would like to pursue in my musical career. I wanted to make an album filled with songs I like, and work with musicians who inspired me. When deciding who to collaborate with for this album, I chose artists who can express the songs best.[6]

Jonghyun's song, "Beautiful Tonight", was composed as early as 2012 and was inspired by the view of the moon as he was walking home from work one night.[7]

On January 7, Jonghyun released his self-composed song "Déjà-Boo" which is co-produced by Zion.T who also features on the track. The song is a described as a "retro funk song with a synthesizer comping melody and the funk rhythm of a bass".[8][9]

On January 8, Jonghyun pre-released "Love Belt", another self-composed song which is a collaborative track with Younha, on MBC FM4U's broadcast of "Blue Night".[10] The official music video for "Crazy (Guilty Pleasure)" was released on the same day, it features the rapper Iron who received attention with his performance on Mnet's survival show Show Me The Money 3.[11][12] The concept of the music video takes after the name of the title song, guilty pleasure which means to enjoy something that you shouldn't. Jonghyun portrays a man who is head over heels for an alluring woman.[13] Jonghyun started his official album promotions on KBS′ Music Bank on January 9.[14] Jonghyun's music video to "Crazy (Guilty Pleasure)" was the most watched K-pop video in America and in the world for January 2015.[15] As of 2015 the album has sold around 74,000 copies in South Korea.[16]

Credits adapted from official artist page.[17]

All lyrics written by Jonghyun except track 2 which is co-written with Iron, and track 3 which is co-written with Wheesung.