To start learning Secret Number, Jeong Donghwan, Melomance, Kim Min Seok - (사랑인가 봐, A Business Proposal OST Part.5) Love, Maybe chords, delve into these chords sequence to get the song's feel: E, B, E, Ebm, Abm, E, Gb, Dbm, E, Ebm, B, Gb, Abm and Ebm. Start with a comfortable 42 BPM and as you become proficient, aim for the song's BPM of 86. To match your vocal range and chord inclination, adjust the capo in line with the key: B Major.