The debut song " BUTTERFLY " is a superb R&B song with a luxurious production team including producer Matt Cab , DJ UPPERCUT top line, Nijiiro Samurai Zuma, and Oriya Fujita. In the lyrics, it is also written as `` butterflies ,'' and it is also used to mean the emotional feeling of `` throbbing in the chest '' or `` throbbing, '' expressing a sweet and sad love.