"Lion Heart" was described as a soul pop-inspired bubblegum pop song by Billboard.[1] It embraces a 1960s American retro sound and has a jazzy melody as well as "an ear-grabbing bass line".[2][3] Lyrically, the song talks about women falling in love with men who have a cheating heart and how they try to tame him like taming a lion.[4]
The music video was released on August 18, 2015.[5] The music video narrates a story where the members of Girls' Generation each fall in love with a male protagonist, who turns out to be the same man (with his head being that of a lion, representing the song's conceptual "lion heart/lyin' heart" pun). They become upset and team up against him, then go on to reject further advances from him separately.[1] The song was choreographed by the American choreographer Tony Testa & SM Entertainment's choreographer Shim Jaewon.[6] It became third most viewed music video on YouTube by a South Korean act in August 2015.[7]
Billboard praised the song for its retro themes and shifting of member roles saying "But what is new, musically, is the division of lines -- namely when Yuri, a member who typically only chimes in with a line or two, gets to handle a majority of the second chorus. It's a decision that further shows how Girls' Generation is embracing change in their eighth year..."[8] The song was deemed the 7th best K-pop single of 2015 by PopMatters.[9] Meanwhile, Idolator chose it as the 24th best K-pop song of the year.[10]
"Lion Heart" received 14 music program awards in South Korea. It was nominated for Song of the Month (September) at the 5th Gaon Chart Music Awards, but lost to iKon's "My Type". It was one of the Digital Song Bonsang winners at the 30th Golden Disc Awards and was nominated for Digital Daesang.[11]
