The second EP from K-pop crew BTS, Skool Luv Affair closed the group's "school trilogy" with a rap-heavy bang. Further refining their sound as they continued their steady rise to world domination, the ten-track effort featured fan favorites like "Intro: Skool Luv Affair" -- which got a second life at the end of the decade with "Intro: Persona" -- and the booming "Boy in Luv." As a showcase for their rap skills, tracks such as "BTS Cypher Pt.2: Triptych" and "Spine Breaker" find the boys at a stage where they hadn't yet started the transition to a more polished, dance-pop sound, still retaining the scrappy underdog spirit that endeared them to fans in the first place. Originally released in early 2014, the set was reissued for fans in late 2020 and peaked just outside the Top Ten on the Billboard 200.