Lilac-haired, 16-year-old Billie Eilish is Webster’s definition of a paradox. While her angelic voice serenades her heartfelt ballads, the allusion to violence throughout her baleful productions suggests that hell takes form in a teenage girl. Her Oct. 23 stop at the Roseland Theater, a music venue in downtown Portland as a part of her Where’s My Mind tour, was no different, as Eilish’s offhand switches of rhapsodizing rage to calm and quiet melodies left the audience in awe.

Before Eilish appeared on stage, her brother, Finneas kicked off the show with a few of his own musical creations. As he presented the audience with a composition of his own songs, mainly consisting of sultry rock numbers, it became clear that talent runs throughout the family. Despite taking on completely different styles of music, the ability to present emotion in the form of rhythms and lyrics remained a constant between the siblings. Considering that Finneas wrote or co-wrote all of the songs on Eilish’s EP “don’t smile at me,” fans were eager to sway along, even if unfamiliar with most of his music.

The crowd attending was overwhelmingly female and young, so much so that the bar stools crowding the venue’s balcony were populated with parent chaperones, marveling at the hysteria which so closely resembled that of their early years, where the same energy blasted at the arrival of The Backstreet Boys songs.

Eilish finally emerged amidst the stage fog to deafening screams, dressed in her signature outfit: basketball shorts, an oversized tee-shirt and gold chains. Her hip-hop inspired attire is an example of how Eilish subverts expectations. She made the most of the rather small stage with a spider-shaped sculpture, in both the spirit of the Halloween season and the music video of her recent single, “you should see me in a crown,” where the music video opens with a spider crawling from her mouth. She was surrounded by round, color changing light bulbs that flashed along to the music’s rhythm changes.

As Eilish sent the crowd into a delirium through anger’s anthem, “COPYCAT,” a self-explanatory track where her angsty lyrics confronting irritability and lack of unoriginality found within others, brought out the hellish side of the audience. This was followed by the track’s reflection, “idontwannabeyouanymore,” a song conveying the struggle of being unsatisfied with the person staring back at you in the mirror.

When it came time for her to perform an unreleased track, she hinted at the crowd to put away their phones saying, “for this one, just look up and look at me,” prompting everyone to be present and savor the soft ballad that sometimes rose only above a whisper. The audience mellowed down, as their eyes began to fill with tears at the song dedicated to her recently departed friend.

Encore Billie, encore.