People who fell in love with Ulven’s initial lo-fi bedroom-pop aesthetic may not be fully on-board with this new sound, but Serotonin is more ambitious than anything that she she has ever released before. It sees her truly transform from being trapped under the label of bedroom-pop into an artist capable of much more. This stylistic shift was assisted by FINNEAS, brother and producer of Billie Eilish, who co-produced the track. He brings a novel, darker pop sound to Ulven’s work, similar to the sound of some of Eilish’s work. She sounds comfortable and confident on top of this dark and pounding pop instrumental