내가 짝사랑이라니!아하 (A-Ha)는 효린이 처음으로 선보이는 겨울 시즌송으로, 벨소리와 리듬을 메인으로 한 Pop Dance 장르의 곡이다.[Credit]Executive Produced by bridgeExecutive Producer Heesun JooCreative Director Seunghee leeLyrics by 김이나Composed by 로코, 베리, 이유진Arranged by 이유진Recorded by 장민 @ M Creative SoundDigital Edited by 장민 @ M Creative SoundMixed by 김현곤 @ DoobDoob StudioMastered by 권남우 @ 821 Sound MasteringChoreographer Nicole Kirkland